Constants! Constants everywhere! (#9286)

Aggressively apply the const lint.
diff --git a/examples/flutter_gallery/lib/demo/colors_demo.dart b/examples/flutter_gallery/lib/demo/colors_demo.dart
index 0aa49ee..0709296 100644
--- a/examples/flutter_gallery/lib/demo/colors_demo.dart
+++ b/examples/flutter_gallery/lib/demo/colors_demo.dart
@@ -125,7 +125,7 @@
       child: new Scaffold(
         appBar: new AppBar(
           elevation: 0,
-          title: new Text('Colors'),
+          title: const Text('Colors'),
           bottom: new TabBar(
             isScrollable: true,
             tabs: allPalettes.map((Palette swatch) => new Tab(text: swatch.name)).toList(),
diff --git a/examples/flutter_gallery/lib/demo/contacts_demo.dart b/examples/flutter_gallery/lib/demo/contacts_demo.dart
index b6d9c9e..0e9a9b1 100644
--- a/examples/flutter_gallery/lib/demo/contacts_demo.dart
+++ b/examples/flutter_gallery/lib/demo/contacts_demo.dart
@@ -113,11 +113,11 @@
               floating: _appBarBehavior == AppBarBehavior.floating,
               actions: <Widget>[
                 new IconButton(
-                  icon: new Icon(Icons.create),
+                  icon: const Icon(Icons.create),
                   tooltip: 'Edit',
                   onPressed: () {
                     _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                      content: new Text('This is actually just a demo. Editing isn\'t supported.')
+                      content: const Text('This is actually just a demo. Editing isn\'t supported.')
                     ));
                   },
                 ),
@@ -130,21 +130,21 @@
                   itemBuilder: (BuildContext context) => <PopupMenuItem<AppBarBehavior>>[
                     new PopupMenuItem<AppBarBehavior>(
                       value: AppBarBehavior.normal,
-                      child: new Text('App bar scrolls away')
+                      child: const Text('App bar scrolls away')
                     ),
                     new PopupMenuItem<AppBarBehavior>(
                       value: AppBarBehavior.pinned,
-                      child: new Text('App bar stays put')
+                      child: const Text('App bar stays put')
                     ),
                     new PopupMenuItem<AppBarBehavior>(
                       value: AppBarBehavior.floating,
-                      child: new Text('App bar floats')
+                      child: const Text('App bar floats')
                     ),
                   ],
                 ),
               ],
               flexibleSpace: new FlexibleSpaceBar(
-                title: new Text('Ali Connors'),
+                title: const Text('Ali Connors'),
                 background: new Stack(
                   children: <Widget>[
                     new Image.asset(
@@ -154,7 +154,7 @@
                     ),
                     // This gradient ensures that the toolbar icons are distinct
                     // against the background image.
-                    new DecoratedBox(
+                    const DecoratedBox(
                       decoration: const BoxDecoration(
                         gradient: const LinearGradient(
                           begin: const FractionalOffset(0.5, 0.0),
@@ -177,7 +177,7 @@
                       tooltip: 'Send message',
                       onPressed: () {
                         _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                          content: new Text('Pretend that this opened your SMS application.')
+                          content: const Text('Pretend that this opened your SMS application.')
                         ));
                       },
                       lines: <String>[
@@ -190,7 +190,7 @@
                       tooltip: 'Send message',
                       onPressed: () {
                         _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                          content: new Text('In this demo, this button doesn\'t do anything.')
+                          content: const Text('In this demo, this button doesn\'t do anything.')
                         ));
                       },
                       lines: <String>[
@@ -203,7 +203,7 @@
                       tooltip: 'Send message',
                       onPressed: () {
                         _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                          content: new Text('Imagine if you will, a messaging application.')
+                          content: const Text('Imagine if you will, a messaging application.')
                         ));
                       },
                       lines: <String>[
@@ -221,7 +221,7 @@
                       tooltip: 'Send personal e-mail',
                       onPressed: () {
                         _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                          content: new Text('Here, your e-mail application would open.')
+                          content: const Text('Here, your e-mail application would open.')
                         ));
                       },
                       lines: <String>[
@@ -234,7 +234,7 @@
                       tooltip: 'Send work e-mail',
                       onPressed: () {
                         _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                          content: new Text('This is a demo, so this button does not actually work.')
+                          content: const Text('This is a demo, so this button does not actually work.')
                         ));
                       },
                       lines: <String>[
@@ -252,7 +252,7 @@
                       tooltip: 'Open map',
                       onPressed: () {
                         _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                          content: new Text('This would show a map of San Francisco.')
+                          content: const Text('This would show a map of San Francisco.')
                         ));
                       },
                       lines: <String>[
@@ -266,7 +266,7 @@
                       tooltip: 'Open map',
                       onPressed: () {
                         _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                          content: new Text('This would show a map of Mountain View.')
+                          content: const Text('This would show a map of Mountain View.')
                         ));
                       },
                       lines: <String>[
@@ -280,7 +280,7 @@
                       tooltip: 'Open map',
                       onPressed: () {
                         _scaffoldKey.currentState.showSnackBar(new SnackBar(
-                          content: new Text('This would also show a map, if this was not a demo.')
+                          content: const Text('This would also show a map, if this was not a demo.')
                         ));
                       },
                       lines: <String>[
diff --git a/examples/flutter_gallery/lib/demo/cupertino/cupertino_activity_indicator_demo.dart b/examples/flutter_gallery/lib/demo/cupertino/cupertino_activity_indicator_demo.dart
index 28d0b93..bcd717f 100644
--- a/examples/flutter_gallery/lib/demo/cupertino/cupertino_activity_indicator_demo.dart
+++ b/examples/flutter_gallery/lib/demo/cupertino/cupertino_activity_indicator_demo.dart
@@ -12,7 +12,7 @@
   Widget build(BuildContext context) {
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Cupertino Activity Indicator'),
+        title: const Text('Cupertino Activity Indicator'),
       ),
       body: new Center(
         child: new CupertinoActivityIndicator(),
diff --git a/examples/flutter_gallery/lib/demo/cupertino/cupertino_buttons_demo.dart b/examples/flutter_gallery/lib/demo/cupertino/cupertino_buttons_demo.dart
index aeee815..b45a203 100644
--- a/examples/flutter_gallery/lib/demo/cupertino/cupertino_buttons_demo.dart
+++ b/examples/flutter_gallery/lib/demo/cupertino/cupertino_buttons_demo.dart
@@ -21,13 +21,13 @@
   Widget build(BuildContext context) {
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Cupertino Buttons'),
+        title: const Text('Cupertino Buttons'),
       ),
       body: new Column(
         children: <Widget> [
-          new Padding(
+          const Padding(
             padding: const EdgeInsets.all(16.0),
-            child: new Text('iOS themed buttons are flat. They can have borders or backgrounds but '
+            child: const Text('iOS themed buttons are flat. They can have borders or backgrounds but '
                 'only when necessary.'),
           ),
           new Expanded(
@@ -35,36 +35,36 @@
               mainAxisAlignment: MainAxisAlignment.center,
               children: <Widget> [
                 new Text(_pressedCount > 0 ? "Button pressed $_pressedCount times" : " "),
-                new Padding(padding: const EdgeInsets.all(12.0)),
+                const Padding(padding: const EdgeInsets.all(12.0)),
                 new Align(
                   alignment: const FractionalOffset(0.5, 0.4),
                   child: new Row(
                     mainAxisSize: MainAxisSize.min,
                     children: <Widget>[
                       new CupertinoButton(
-                        child: new Text('Cupertino Button'),
+                        child: const Text('Cupertino Button'),
                         onPressed: () {
                           setState(() {_pressedCount++;});
                         }
                       ),
                       new CupertinoButton(
-                        child: new Text('Disabled'),
+                        child: const Text('Disabled'),
                         onPressed: null,
                       ),
                     ],
                   ),
                 ),
-                new Padding(padding: const EdgeInsets.all(12.0)),
+                const Padding(padding: const EdgeInsets.all(12.0)),
                 new CupertinoButton(
-                  child: new Text('With Background'),
+                  child: const Text('With Background'),
                   color: _kBlue,
                   onPressed: () {
                     setState(() {_pressedCount++;});
                   }
                 ),
-                new Padding(padding: const EdgeInsets.all(12.0)),
+                const Padding(padding: const EdgeInsets.all(12.0)),
                 new CupertinoButton(
-                  child: new Text('Disabled'),
+                  child: const Text('Disabled'),
                   color: _kBlue,
                   onPressed: null,
                 ),
diff --git a/examples/flutter_gallery/lib/demo/cupertino/cupertino_dialog_demo.dart b/examples/flutter_gallery/lib/demo/cupertino/cupertino_dialog_demo.dart
index e808557..5013032 100644
--- a/examples/flutter_gallery/lib/demo/cupertino/cupertino_dialog_demo.dart
+++ b/examples/flutter_gallery/lib/demo/cupertino/cupertino_dialog_demo.dart
@@ -37,27 +37,27 @@
     return new Scaffold(
       key: _scaffoldKey,
       appBar: new AppBar(
-        title: new Text('Cupertino Dialogs'),
+        title: const Text('Cupertino Dialogs'),
       ),
       body: new ListView(
         padding: const EdgeInsets.symmetric(vertical: 24.0, horizontal: 72.0),
         children: <Widget> [
           new CupertinoButton(
-            child: new Text('Alert'),
+            child: const Text('Alert'),
             color: _kBlue,
             onPressed: () {
               showDemoDialog<String>(
                 context: context,
                 child: new CupertinoAlertDialog(
-                  content: new Text('Discard draft?'),
+                  content: const Text('Discard draft?'),
                   actions: <Widget>[
                     new CupertinoDialogAction(
-                      child: new Text('Discard'),
+                      child: const Text('Discard'),
                       isDestructive: true,
                       onPressed: () { Navigator.pop(context, 'OK'); }
                     ),
                     new CupertinoDialogAction(
-                      child: new Text('Cancel', style: const TextStyle(fontWeight: FontWeight.w600)),
+                      child: const Text('Cancel', style: const TextStyle(fontWeight: FontWeight.w600)),
                       onPressed: () { Navigator.pop(context, 'Cancel'); }
                     ),
                   ]
@@ -65,27 +65,27 @@
               );
             },
           ),
-          new Padding(padding: const EdgeInsets.all(8.0)),
+          const Padding(padding: const EdgeInsets.all(8.0)),
           new CupertinoButton(
-            child: new Text('Alert with Title'),
+            child: const Text('Alert with Title'),
             color: _kBlue,
             padding: const EdgeInsets.symmetric(vertical: 16.0, horizontal: 36.0),
             onPressed: () {
               showDemoDialog<String>(
                 context: context,
                 child: new CupertinoAlertDialog(
-                  title: new Text('Allow "Maps" to access your location while you use the app?'),
-                  content: new Text(
+                  title: const Text('Allow "Maps" to access your location while you use the app?'),
+                  content: const Text(
                     'Your current location will be displayed on the map and used for directions, '
                     'nearby search results, and estimated travel times.'
                   ),
                   actions: <Widget>[
                     new CupertinoDialogAction(
-                      child: new Text('Don\'t Allow'),
+                      child: const Text('Don\'t Allow'),
                       onPressed: () { Navigator.pop(context, 'Disallow'); }
                     ),
                     new CupertinoDialogAction(
-                      child: new Text('Allow'),
+                      child: const Text('Allow'),
                       onPressed: () { Navigator.pop(context, 'Allow'); }
                     ),
                   ]
diff --git a/examples/flutter_gallery/lib/demo/cupertino/cupertino_slider_demo.dart b/examples/flutter_gallery/lib/demo/cupertino/cupertino_slider_demo.dart
index 13971cd..79cb7d0 100644
--- a/examples/flutter_gallery/lib/demo/cupertino/cupertino_slider_demo.dart
+++ b/examples/flutter_gallery/lib/demo/cupertino/cupertino_slider_demo.dart
@@ -20,7 +20,7 @@
   Widget build(BuildContext context) {
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Cupertino Sliders'),
+        title: const Text('Cupertino Sliders'),
       ),
       body: new Center(
         child: new Column(
@@ -39,7 +39,7 @@
                     });
                   }
                 ),
-                new Text('Cupertino Continuous'),
+                const Text('Cupertino Continuous'),
               ]
             ),
             new Column(
@@ -56,7 +56,7 @@
                     });
                   }
                 ),
-                new Text('Cupertino Discrete'),
+                const Text('Cupertino Discrete'),
               ]
             ),
           ],
diff --git a/examples/flutter_gallery/lib/demo/cupertino/cupertino_switch_demo.dart b/examples/flutter_gallery/lib/demo/cupertino/cupertino_switch_demo.dart
index dd2df03..c666156 100644
--- a/examples/flutter_gallery/lib/demo/cupertino/cupertino_switch_demo.dart
+++ b/examples/flutter_gallery/lib/demo/cupertino/cupertino_switch_demo.dart
@@ -20,7 +20,7 @@
   Widget build(BuildContext context) {
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Cupertino Switch'),
+        title: const Text('Cupertino Switch'),
       ),
       body: new Center(
         child:  new CupertinoSwitch(
diff --git a/examples/flutter_gallery/lib/demo/material/bottom_navigation_demo.dart b/examples/flutter_gallery/lib/demo/material/bottom_navigation_demo.dart
index 4cbe54f..7acc30e 100644
--- a/examples/flutter_gallery/lib/demo/material/bottom_navigation_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/bottom_navigation_demo.dart
@@ -23,7 +23,7 @@
        ) {
     _animation = new CurvedAnimation(
       parent: controller,
-      curve: new Interval(0.5, 1.0, curve: Curves.fastOutSlowIn),
+      curve: const Interval(0.5, 1.0, curve: Curves.fastOutSlowIn),
     );
   }
 
@@ -96,32 +96,32 @@
     super.initState();
     _navigationViews = <NavigationIconView>[
       new NavigationIconView(
-        icon: new Icon(Icons.access_alarm),
-        title: new Text('Alarm'),
+        icon: const Icon(Icons.access_alarm),
+        title: const Text('Alarm'),
         color: Colors.deepPurple,
         vsync: this,
       ),
       new NavigationIconView(
         icon: new CustomIcon(),
-        title: new Text('Box'),
+        title: const Text('Box'),
         color: Colors.deepOrange,
         vsync: this,
       ),
       new NavigationIconView(
-        icon: new Icon(Icons.cloud),
-        title: new Text('Cloud'),
+        icon: const Icon(Icons.cloud),
+        title: const Text('Cloud'),
         color: Colors.teal,
         vsync: this,
       ),
       new NavigationIconView(
-        icon: new Icon(Icons.favorite),
-        title: new Text('Favorites'),
+        icon: const Icon(Icons.favorite),
+        title: const Text('Favorites'),
         color: Colors.indigo,
         vsync: this,
       ),
       new NavigationIconView(
-        icon: new Icon(Icons.event_available),
-        title: new Text('Event'),
+        icon: const Icon(Icons.event_available),
+        title: const Text('Event'),
         color: Colors.pink,
         vsync: this,
       )
@@ -183,7 +183,7 @@
 
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Bottom navigation'),
+        title: const Text('Bottom navigation'),
         actions: <Widget>[
           new PopupMenuButton<BottomNavigationBarType>(
             onSelected: (BottomNavigationBarType value) {
@@ -194,11 +194,11 @@
             itemBuilder: (BuildContext context) => <PopupMenuItem<BottomNavigationBarType>>[
               new PopupMenuItem<BottomNavigationBarType>(
                 value: BottomNavigationBarType.fixed,
-                child: new Text('Fixed'),
+                child: const Text('Fixed'),
               ),
               new PopupMenuItem<BottomNavigationBarType>(
                 value: BottomNavigationBarType.shifting,
-                child: new Text('Shifting'),
+                child: const Text('Shifting'),
               )
             ],
           )
diff --git a/examples/flutter_gallery/lib/demo/material/buttons_demo.dart b/examples/flutter_gallery/lib/demo/material/buttons_demo.dart
index f191300..c3aafd6 100644
--- a/examples/flutter_gallery/lib/demo/material/buttons_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/buttons_demo.dart
@@ -95,13 +95,13 @@
         mainAxisSize: MainAxisSize.min,
         children: <Widget>[
           new RaisedButton(
-            child: new Text('RAISED BUTTON'),
+            child: const Text('RAISED BUTTON'),
             onPressed: () {
               // Perform some action
             },
           ),
           new RaisedButton(
-            child: new Text('DISABLED'),
+            child: const Text('DISABLED'),
             onPressed: null,
           )
         ],
@@ -116,13 +116,13 @@
         mainAxisSize: MainAxisSize.min,
         children: <Widget>[
           new FlatButton(
-            child: new Text('FLAT BUTTON'),
+            child: const Text('FLAT BUTTON'),
             onPressed: () {
               // Perform some action
             },
           ),
           new FlatButton(
-            child: new Text('DISABLED'),
+            child: const Text('DISABLED'),
             onPressed: null,
           )
         ],
@@ -142,7 +142,7 @@
         mainAxisAlignment: MainAxisAlignment.start,
         children: <Widget>[
           new ListTile(
-            title: new Text('Simple dropdown:'),
+            title: const Text('Simple dropdown:'),
             trailing: new DropdownButton<String>(
               value: dropdown1Value,
               onChanged: (String newValue) {
@@ -162,10 +162,10 @@
             height: 24.0,
           ),
           new ListTile(
-            title: new Text('Dropdown with a hint:'),
+            title: const Text('Dropdown with a hint:'),
             trailing: new DropdownButton<String>(
               value: dropdown2Value,
-              hint: new Text('Choose'),
+              hint: const Text('Choose'),
               onChanged: (String newValue) {
                 setState(() {
                   dropdown2Value = newValue;
@@ -183,7 +183,7 @@
             height: 24.0,
           ),
           new ListTile(
-            title: new Text('Scrollable dropdown:'),
+            title: const Text('Scrollable dropdown:'),
             trailing: new DropdownButton<String>(
               value: dropdown3Value,
               onChanged: (String newValue) {
@@ -218,14 +218,14 @@
         mainAxisSize: MainAxisSize.min,
         children: <Widget>[
           new IconButton(
-            icon: new Icon(Icons.thumb_up),
+            icon: const Icon(Icons.thumb_up),
             onPressed: () {
               setState(() => iconButtonToggle = !iconButtonToggle);
             },
             color: iconButtonToggle ? Theme.of(context).primaryColor : null,
           ),
-          new IconButton(
-            icon: new Icon(Icons.thumb_up),
+          const IconButton(
+            icon: const Icon(Icons.thumb_up),
             onPressed: null,
           )
         ]
@@ -239,7 +239,7 @@
     return new Align(
       alignment: const FractionalOffset(0.5, 0.4),
       child: new FloatingActionButton(
-        child: new Icon(Icons.add),
+        child: const Icon(Icons.add),
         onPressed: () {
           // Perform some action
         },
diff --git a/examples/flutter_gallery/lib/demo/material/cards_demo.dart b/examples/flutter_gallery/lib/demo/material/cards_demo.dart
index fdc637f..a34d337 100644
--- a/examples/flutter_gallery/lib/demo/material/cards_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/cards_demo.dart
@@ -116,12 +116,12 @@
                 alignment: MainAxisAlignment.start,
                 children: <Widget>[
                   new FlatButton(
-                    child: new Text('SHARE'),
+                    child: const Text('SHARE'),
                     textColor: Colors.amber.shade500,
                     onPressed: () { /* do nothing */ },
                   ),
                   new FlatButton(
-                    child: new Text('EXPLORE'),
+                    child: const Text('EXPLORE'),
                     textColor: Colors.amber.shade500,
                     onPressed: () { /* do nothing */ },
                   ),
@@ -142,7 +142,7 @@
   Widget build(BuildContext context) {
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Travel stream')
+        title: const Text('Travel stream')
       ),
       body: new ListView(
         itemExtent: TravelDestinationItem.height,
diff --git a/examples/flutter_gallery/lib/demo/material/chip_demo.dart b/examples/flutter_gallery/lib/demo/material/chip_demo.dart
index 838d30b..86be8a3 100644
--- a/examples/flutter_gallery/lib/demo/material/chip_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/chip_demo.dart
@@ -23,24 +23,24 @@
   @override
   Widget build(BuildContext context) {
     final List<Widget> chips = <Widget>[
-      new Chip(
-        label: new Text('Apple')
+      const Chip(
+        label: const Text('Apple')
       ),
       new Chip(
-        avatar: new CircleAvatar(child: new Text('B')),
-        label: new Text('Blueberry')
+        avatar: new CircleAvatar(child: const Text('B')),
+        label: const Text('Blueberry')
       ),
     ];
 
     if (_showBananas) {
       chips.add(new Chip(
-        label: new Text('Bananas'),
+        label: const Text('Bananas'),
         onDeleted: _deleteBananas
       ));
     }
 
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Chips')),
+      appBar: new AppBar(title: const Text('Chips')),
       body: new ListView(
         children: chips.map((Widget widget) {
           return new Container(
diff --git a/examples/flutter_gallery/lib/demo/material/data_table_demo.dart b/examples/flutter_gallery/lib/demo/material/data_table_demo.dart
index c2eacdf..7bfd0f7 100644
--- a/examples/flutter_gallery/lib/demo/material/data_table_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/data_table_demo.dart
@@ -164,12 +164,12 @@
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Data tables')),
+      appBar: new AppBar(title: const Text('Data tables')),
       body: new ListView(
         padding: const EdgeInsets.all(20.0),
         children: <Widget>[
           new PaginatedDataTable(
-            header: new Text('Nutrition'),
+            header: const Text('Nutrition'),
             rowsPerPage: _rowsPerPage,
             onRowsPerPageChanged: (int value) { setState(() { _rowsPerPage = value; }); },
             sortColumnIndex: _sortColumnIndex,
@@ -177,43 +177,43 @@
             onSelectAll: _dessertsDataSource._selectAll,
             columns: <DataColumn>[
               new DataColumn(
-                label: new Text('Dessert (100g serving)'),
+                label: const Text('Dessert (100g serving)'),
                 onSort: (int columnIndex, bool ascending) => _sort<String>((Dessert d) => d.name, columnIndex, ascending)
               ),
               new DataColumn(
-                label: new Text('Calories'),
+                label: const Text('Calories'),
                 tooltip: 'The total amount of food energy in the given serving size.',
                 numeric: true,
                 onSort: (int columnIndex, bool ascending) => _sort<num>((Dessert d) => d.calories, columnIndex, ascending)
               ),
               new DataColumn(
-                label: new Text('Fat (g)'),
+                label: const Text('Fat (g)'),
                 numeric: true,
                 onSort: (int columnIndex, bool ascending) => _sort<num>((Dessert d) => d.fat, columnIndex, ascending)
               ),
               new DataColumn(
-                label: new Text('Carbs (g)'),
+                label: const Text('Carbs (g)'),
                 numeric: true,
                 onSort: (int columnIndex, bool ascending) => _sort<num>((Dessert d) => d.carbs, columnIndex, ascending)
               ),
               new DataColumn(
-                label: new Text('Protein (g)'),
+                label: const Text('Protein (g)'),
                 numeric: true,
                 onSort: (int columnIndex, bool ascending) => _sort<num>((Dessert d) => d.protein, columnIndex, ascending)
               ),
               new DataColumn(
-                label: new Text('Sodium (mg)'),
+                label: const Text('Sodium (mg)'),
                 numeric: true,
                 onSort: (int columnIndex, bool ascending) => _sort<num>((Dessert d) => d.sodium, columnIndex, ascending)
               ),
               new DataColumn(
-                label: new Text('Calcium (%)'),
+                label: const Text('Calcium (%)'),
                 tooltip: 'The amount of calcium as a percentage of the recommended daily amount.',
                 numeric: true,
                 onSort: (int columnIndex, bool ascending) => _sort<num>((Dessert d) => d.calcium, columnIndex, ascending)
               ),
               new DataColumn(
-                label: new Text('Iron (%)'),
+                label: const Text('Iron (%)'),
                 numeric: true,
                 onSort: (int columnIndex, bool ascending) => _sort<num>((Dessert d) => d.iron, columnIndex, ascending)
               ),
diff --git a/examples/flutter_gallery/lib/demo/material/date_and_time_picker_demo.dart b/examples/flutter_gallery/lib/demo/material/date_and_time_picker_demo.dart
index 02590f8..de847c8 100644
--- a/examples/flutter_gallery/lib/demo/material/date_and_time_picker_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/date_and_time_picker_demo.dart
@@ -129,7 +129,7 @@
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Date and time pickers')),
+      appBar: new AppBar(title: const Text('Date and time pickers')),
       body: new DropdownButtonHideUnderline(
         child: new ListView(
           padding: const EdgeInsets.all(16.0),
diff --git a/examples/flutter_gallery/lib/demo/material/dialog_demo.dart b/examples/flutter_gallery/lib/demo/material/dialog_demo.dart
index 7210568..a2b17e5 100644
--- a/examples/flutter_gallery/lib/demo/material/dialog_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/dialog_demo.dart
@@ -87,13 +87,13 @@
     return new Scaffold(
       key: _scaffoldKey,
       appBar: new AppBar(
-        title: new Text('Dialogs')
+        title: const Text('Dialogs')
       ),
       body: new ListView(
         padding: const EdgeInsets.symmetric(vertical: 24.0, horizontal: 72.0),
         children: <Widget>[
           new RaisedButton(
-            child: new Text('ALERT'),
+            child: const Text('ALERT'),
             onPressed: () {
               showDemoDialog<DialogDemoAction>(
                 context: context,
@@ -104,11 +104,11 @@
                   ),
                   actions: <Widget>[
                     new FlatButton(
-                      child: new Text('CANCEL'),
+                      child: const Text('CANCEL'),
                       onPressed: () { Navigator.pop(context, DialogDemoAction.cancel); }
                     ),
                     new FlatButton(
-                      child: new Text('DISCARD'),
+                      child: const Text('DISCARD'),
                       onPressed: () { Navigator.pop(context, DialogDemoAction.discard); }
                     )
                   ]
@@ -117,23 +117,23 @@
             }
           ),
           new RaisedButton(
-            child: new Text('ALERT WITH TITLE'),
+            child: const Text('ALERT WITH TITLE'),
             onPressed: () {
               showDemoDialog<DialogDemoAction>(
                 context: context,
                 child: new AlertDialog(
-                  title: new Text('Use Google\'s location service?'),
+                  title: const Text('Use Google\'s location service?'),
                   content: new Text(
                     _alertWithTitleText,
                     style: dialogTextStyle
                   ),
                   actions: <Widget>[
                     new FlatButton(
-                      child: new Text('DISAGREE'),
+                      child: const Text('DISAGREE'),
                       onPressed: () { Navigator.pop(context, DialogDemoAction.disagree); }
                     ),
                     new FlatButton(
-                      child: new Text('AGREE'),
+                      child: const Text('AGREE'),
                       onPressed: () { Navigator.pop(context, DialogDemoAction.agree); }
                     )
                   ]
@@ -142,12 +142,12 @@
             }
           ),
           new RaisedButton(
-            child: new Text('SIMPLE'),
+            child: const Text('SIMPLE'),
             onPressed: () {
               showDemoDialog<String>(
                 context: context,
                 child: new SimpleDialog(
-                  title: new Text('Set backup account'),
+                  title: const Text('Set backup account'),
                   children: <Widget>[
                     new DialogDemoItem(
                       icon: Icons.account_circle,
@@ -172,7 +172,7 @@
             }
           ),
           new RaisedButton(
-            child: new Text('CONFIRMATION'),
+            child: const Text('CONFIRMATION'),
             onPressed: () {
               showTimePicker(
                 context: context,
@@ -189,7 +189,7 @@
             }
           ),
           new RaisedButton(
-            child: new Text('FULLSCREEN'),
+            child: const Text('FULLSCREEN'),
             onPressed: () {
               Navigator.push(context, new MaterialPageRoute<DismissDialogAction>(
                 builder: (BuildContext context) => new FullScreenDialogDemo(),
diff --git a/examples/flutter_gallery/lib/demo/material/drawer_demo.dart b/examples/flutter_gallery/lib/demo/material/drawer_demo.dart
index 0ed5761..b922355 100644
--- a/examples/flutter_gallery/lib/demo/material/drawer_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/drawer_demo.dart
@@ -68,7 +68,7 @@
   void _showNotImplementedMessage() {
     Navigator.of(context).pop(); // Dismiss the drawer.
     _scaffoldKey.currentState.showSnackBar(new SnackBar(
-      content: new Text("The drawer's items don't do anything")
+      content: const Text("The drawer's items don't do anything")
     ));
   }
 
@@ -85,14 +85,14 @@
             Navigator.pop(context);
           },
         ),
-        title: new Text('Navigation drawer'),
+        title: const Text('Navigation drawer'),
       ),
       drawer: new Drawer(
         child: new ListView(
           children: <Widget>[
             new UserAccountsDrawerHeader(
-              accountName: new Text('Zach Widget'),
-              accountEmail: new Text('zach.widget@example.com'),
+              accountName: const Text('Zach Widget'),
+              accountEmail: const Text('zach.widget@example.com'),
               currentAccountPicture: new CircleAvatar(backgroundImage: new AssetImage(_kAsset0)),
               otherAccountsPictures: <Widget>[
                 new CircleAvatar(backgroundImage: new AssetImage(_kAsset1)),
@@ -134,13 +134,13 @@
                         crossAxisAlignment: CrossAxisAlignment.stretch,
                         children: <Widget>[
                           new ListTile(
-                            leading: new Icon(Icons.add),
-                            title: new Text('Add account'),
+                            leading: const Icon(Icons.add),
+                            title: const Text('Add account'),
                             onTap: _showNotImplementedMessage,
                           ),
                           new ListTile(
-                            leading: new Icon(Icons.settings),
-                            title: new Text('Manage accounts'),
+                            leading: const Icon(Icons.settings),
+                            title: const Text('Manage accounts'),
                             onTap: _showNotImplementedMessage,
                           ),
                         ],
diff --git a/examples/flutter_gallery/lib/demo/material/expansion_panels_demo.dart b/examples/flutter_gallery/lib/demo/material/expansion_panels_demo.dart
index c2b21f7..197c319 100644
--- a/examples/flutter_gallery/lib/demo/material/expansion_panels_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/expansion_panels_demo.dart
@@ -30,8 +30,8 @@
     return new AnimatedCrossFade(
       firstChild: first,
       secondChild: second,
-      firstCurve: new Interval(0.0, 0.6, curve: Curves.fastOutSlowIn),
-      secondCurve: new Interval(0.4, 1.0, curve: Curves.fastOutSlowIn),
+      firstCurve: const Interval(0.0, 0.6, curve: Curves.fastOutSlowIn),
+      secondCurve: const Interval(0.4, 1.0, curve: Curves.fastOutSlowIn),
       sizeCurve: Curves.fastOutSlowIn,
       crossFadeState: isExpanded ? CrossFadeState.showSecond : CrossFadeState.showFirst,
       duration: const Duration(milliseconds: 200),
@@ -118,7 +118,7 @@
                 margin: const EdgeInsets.only(right: 8.0),
                 child: new FlatButton(
                   onPressed: onCancel,
-                  child: new Text('CANCEL', style: new TextStyle(
+                  child: const Text('CANCEL', style: const TextStyle(
                     color: Colors.black54,
                     fontSize: 15.0,
                     fontWeight: FontWeight.w500
@@ -130,7 +130,7 @@
                 child: new FlatButton(
                   onPressed: onSave,
                   textTheme: ButtonTextTheme.accent,
-                  child: new Text('SAVE')
+                  child: const Text('SAVE')
                 )
               )
             ]
@@ -254,7 +254,7 @@
                                 groupValue: field.value,
                                 onChanged: field.onChanged,
                               ),
-                              new Text('Bahamas')
+                              const Text('Bahamas')
                             ]
                           ),
                           new Row(
@@ -265,7 +265,7 @@
                                 groupValue: field.value,
                                 onChanged: field.onChanged,
                               ),
-                              new Text('Barbados')
+                              const Text('Barbados')
                             ]
                           ),
                           new Row(
@@ -276,7 +276,7 @@
                                 groupValue: field.value,
                                 onChanged: field.onChanged,
                               ),
-                              new Text('Bermuda')
+                              const Text('Bermuda')
                             ]
                           )
                         ]
@@ -334,7 +334,7 @@
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Expansion panels')),
+      appBar: new AppBar(title: const Text('Expansion panels')),
       body: new SingleChildScrollView(
         child: new Container(
           margin: const EdgeInsets.all(24.0),
diff --git a/examples/flutter_gallery/lib/demo/material/full_screen_dialog_demo.dart b/examples/flutter_gallery/lib/demo/material/full_screen_dialog_demo.dart
index a1d0f88..d4061eb 100644
--- a/examples/flutter_gallery/lib/demo/material/full_screen_dialog_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/full_screen_dialog_demo.dart
@@ -57,7 +57,7 @@
                   mainAxisAlignment: MainAxisAlignment.spaceBetween,
                   children: <Widget>[
                     new Text(new DateFormat('EEE, MMM d yyyy').format(date)),
-                    new Icon(Icons.arrow_drop_down, color: Colors.black54),
+                    const Icon(Icons.arrow_drop_down, color: Colors.black54),
                   ]
                 )
               )
@@ -82,7 +82,7 @@
               child: new Row(
                 children: <Widget>[
                   new Text('$time'),
-                  new Icon(Icons.arrow_drop_down, color: Colors.black54),
+                  const Icon(Icons.arrow_drop_down, color: Colors.black54),
                 ]
               )
             )
@@ -122,11 +122,11 @@
         ),
         actions: <Widget>[
           new FlatButton(
-            child: new Text('CANCEL'),
+            child: const Text('CANCEL'),
             onPressed: () { Navigator.pop(context, DismissDialogAction.cancel); }
           ),
           new FlatButton(
-            child: new Text('DISCARD'),
+            child: const Text('DISCARD'),
             onPressed: () {
               Navigator.of(context)
                 ..pop(DismissDialogAction.discard) // pop the cancel/discard dialog
@@ -145,10 +145,10 @@
     return new Scaffold(
       appBar: new AppBar(
         leading: new IconButton(
-          icon: new Icon(Icons.clear),
+          icon: const Icon(Icons.clear),
           onPressed: () { handleDismissButton(context); }
         ),
-        title: new Text('New event'),
+        title: const Text('New event'),
         actions: <Widget> [
           new FlatButton(
             child: new Text('SAVE', style: theme.textTheme.body1.copyWith(color: Colors.white)),
@@ -222,7 +222,7 @@
                     });
                   }
                 ),
-                new Text('All-day')
+                const Text('All-day')
               ]
             )
           )
diff --git a/examples/flutter_gallery/lib/demo/material/grid_list_demo.dart b/examples/flutter_gallery/lib/demo/material/grid_list_demo.dart
index fd09596..a6a37ba 100644
--- a/examples/flutter_gallery/lib/demo/material/grid_list_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/grid_list_demo.dart
@@ -316,22 +316,22 @@
     final Orientation orientation = MediaQuery.of(context).orientation;
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Grid list'),
+        title: const Text('Grid list'),
         actions: <Widget>[
           new PopupMenuButton<GridDemoTileStyle>(
             onSelected: changeTileStyle,
             itemBuilder: (BuildContext context) => <PopupMenuItem<GridDemoTileStyle>>[
               new PopupMenuItem<GridDemoTileStyle>(
                 value: GridDemoTileStyle.imageOnly,
-                child: new Text('Image only'),
+                child: const Text('Image only'),
               ),
               new PopupMenuItem<GridDemoTileStyle>(
                 value: GridDemoTileStyle.oneLine,
-                child: new Text('One line'),
+                child: const Text('One line'),
               ),
               new PopupMenuItem<GridDemoTileStyle>(
                 value: GridDemoTileStyle.twoLine,
-                child: new Text('Two line'),
+                child: const Text('Two line'),
               ),
             ],
           ),
diff --git a/examples/flutter_gallery/lib/demo/material/icons_demo.dart b/examples/flutter_gallery/lib/demo/material/icons_demo.dart
index 57f2cab..4ec2d9c 100644
--- a/examples/flutter_gallery/lib/demo/material/icons_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/icons_demo.dart
@@ -71,7 +71,7 @@
 
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Icons')
+        title: const Text('Icons')
       ),
       body: new IconTheme(
         data: new IconThemeData(opacity: iconOpacity),
diff --git a/examples/flutter_gallery/lib/demo/material/leave_behind_demo.dart b/examples/flutter_gallery/lib/demo/material/leave_behind_demo.dart
index 26d3973..72ccbc1 100644
--- a/examples/flutter_gallery/lib/demo/material/leave_behind_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/leave_behind_demo.dart
@@ -104,13 +104,13 @@
       background: new Container(
         color: theme.primaryColor,
         child: new ListTile(
-          leading: new Icon(Icons.delete, color: Colors.white, size: 36.0)
+          leading: const Icon(Icons.delete, color: Colors.white, size: 36.0)
         )
       ),
       secondaryBackground: new Container(
         color: theme.primaryColor,
         child: new ListTile(
-          trailing: new Icon(Icons.archive, color: Colors.white, size: 36.0)
+          trailing: const Icon(Icons.archive, color: Colors.white, size: 36.0)
         )
       ),
       child: new Container(
@@ -132,30 +132,30 @@
     return new Scaffold(
       key: _scaffoldKey,
       appBar: new AppBar(
-        title: new Text('Swipe to dismiss'),
+        title: const Text('Swipe to dismiss'),
         actions: <Widget>[
           new PopupMenuButton<LeaveBehindDemoAction>(
             onSelected: handleDemoAction,
             itemBuilder: (BuildContext context) => <PopupMenuEntry<LeaveBehindDemoAction>>[
               new PopupMenuItem<LeaveBehindDemoAction>(
                 value: LeaveBehindDemoAction.reset,
-                child: new Text('Reset the list')
+                child: const Text('Reset the list')
               ),
               new PopupMenuDivider(), // ignore: list_element_type_not_assignable, https://github.com/flutter/flutter/issues/5771
               new CheckedPopupMenuItem<LeaveBehindDemoAction>(
                 value: LeaveBehindDemoAction.horizontalSwipe,
                 checked: _dismissDirection == DismissDirection.horizontal,
-                child: new Text('Hoizontal swipe')
+                child: const Text('Hoizontal swipe')
               ),
               new CheckedPopupMenuItem<LeaveBehindDemoAction>(
                 value: LeaveBehindDemoAction.leftSwipe,
                 checked: _dismissDirection == DismissDirection.endToStart,
-                child: new Text('Only swipe left')
+                child: const Text('Only swipe left')
               ),
               new CheckedPopupMenuItem<LeaveBehindDemoAction>(
                 value: LeaveBehindDemoAction.rightSwipe,
                 checked: _dismissDirection == DismissDirection.startToEnd,
-                child: new Text('Only swipe right')
+                child: const Text('Only swipe right')
               )
             ]
           )
diff --git a/examples/flutter_gallery/lib/demo/material/list_demo.dart b/examples/flutter_gallery/lib/demo/material/list_demo.dart
index 1fa98fc..17ed02f 100644
--- a/examples/flutter_gallery/lib/demo/material/list_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/list_demo.dart
@@ -37,15 +37,15 @@
   void _showConfigurationSheet() {
     final PersistentBottomSheetController<Null> bottomSheet = scaffoldKey.currentState.showBottomSheet((BuildContext bottomSheetContext) {
       return new Container(
-        decoration: new BoxDecoration(
-          border: new Border(top: new BorderSide(color: Colors.black26)),
+        decoration: const BoxDecoration(
+          border: const Border(top: const BorderSide(color: Colors.black26)),
         ),
         child: new ListView(
           shrinkWrap: true,
           children: <Widget>[
             new ListTile(
               dense: true,
-              title: new Text('One-line'),
+              title: const Text('One-line'),
               trailing: new Radio<MaterialListType>(
                 value: _showAvatars ? MaterialListType.oneLineWithAvatar : MaterialListType.oneLine,
                 groupValue: _itemType,
@@ -54,7 +54,7 @@
             ),
             new ListTile(
               dense: true,
-              title: new Text('Two-line'),
+              title: const Text('Two-line'),
               trailing: new Radio<MaterialListType>(
                 value: MaterialListType.twoLine,
                 groupValue: _itemType,
@@ -63,7 +63,7 @@
             ),
             new ListTile(
               dense: true,
-              title: new Text('Three-line'),
+              title: const Text('Three-line'),
               trailing: new Radio<MaterialListType>(
                 value: MaterialListType.threeLine,
                 groupValue: _itemType,
@@ -72,7 +72,7 @@
             ),
             new ListTile(
               dense: true,
-              title: new Text('Show avatar'),
+              title: const Text('Show avatar'),
               trailing: new Checkbox(
                 value: _showAvatars,
                 onChanged: (bool value) {
@@ -85,7 +85,7 @@
             ),
             new ListTile(
               dense: true,
-              title: new Text('Show icon'),
+              title: const Text('Show icon'),
               trailing: new Checkbox(
                 value: _showIcons,
                 onChanged: (bool value) {
@@ -98,7 +98,7 @@
             ),
             new ListTile(
               dense: true,
-              title: new Text('Show dividers'),
+              title: const Text('Show dividers'),
               trailing: new Checkbox(
                 value: _showDividers,
                 onChanged: (bool value) {
@@ -111,7 +111,7 @@
             ),
             new ListTile(
               dense: true,
-              title: new Text('Dense layout'),
+              title: const Text('Dense layout'),
               trailing: new Checkbox(
                 value: _dense,
                 onChanged: (bool value) {
@@ -143,9 +143,9 @@
   Widget buildListTile(BuildContext context, String item) {
     Widget secondary;
     if (_itemType == MaterialListType.twoLine) {
-      secondary = new Text("Additional item information.");
+      secondary = const Text("Additional item information.");
     } else if (_itemType == MaterialListType.threeLine) {
-      secondary = new Text(
+      secondary = const Text(
         "Even more additional list item information appears on line three.",
       );
     }
@@ -186,7 +186,7 @@
         title: new Text('Scrolling list\n$itemTypeText$layoutText'),
         actions: <Widget>[
           new IconButton(
-            icon: new Icon(Icons.sort_by_alpha),
+            icon: const Icon(Icons.sort_by_alpha),
             tooltip: 'Sort',
             onPressed: () {
               setState(() {
@@ -196,7 +196,7 @@
             },
           ),
           new IconButton(
-            icon: new Icon(Icons.more_vert),
+            icon: const Icon(Icons.more_vert),
             tooltip: 'Show menu',
             onPressed: _bottomSheet == null ? _showConfigurationSheet : null,
           ),
diff --git a/examples/flutter_gallery/lib/demo/material/menu_demo.dart b/examples/flutter_gallery/lib/demo/material/menu_demo.dart
index edc04da..9a5ffad 100644
--- a/examples/flutter_gallery/lib/demo/material/menu_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/menu_demo.dart
@@ -62,22 +62,22 @@
     return new Scaffold(
       key: _scaffoldKey,
       appBar: new AppBar(
-        title: new Text('Menus'),
+        title: const Text('Menus'),
         actions: <Widget>[
           new PopupMenuButton<String>(
             onSelected: showMenuSelection,
             itemBuilder: (BuildContext context) => <PopupMenuItem<String>>[
               new PopupMenuItem<String>(
                 value: 'Toolbar menu',
-                child: new Text('Toolbar menu')
+                child: const Text('Toolbar menu')
               ),
               new PopupMenuItem<String>(
                 value: 'Right here',
-                child: new Text('Right here')
+                child: const Text('Right here')
               ),
               new PopupMenuItem<String>(
                 value: 'Hooray!',
-                child: new Text('Hooray!')
+                child: const Text('Hooray!')
               ),
             ]
           )
@@ -90,22 +90,22 @@
           // a simple menu with one disabled item. Typically the contents
           // of this "contextual menu" would reflect the app's state.
           new ListTile(
-            title: new Text('An item with a context menu button'),
+            title: const Text('An item with a context menu button'),
             trailing: new PopupMenuButton<String>(
               padding: EdgeInsets.zero,
               onSelected: showMenuSelection,
               itemBuilder: (BuildContext context) => <PopupMenuItem<String>>[
                 new PopupMenuItem<String>(
                   value: _simpleValue1,
-                  child: new Text('Context menu item one')
+                  child: const Text('Context menu item one')
                 ),
                 new PopupMenuItem<String>(
                   enabled: false,
-                  child: new Text('A disabled menu item')
+                  child: const Text('A disabled menu item')
                 ),
                 new PopupMenuItem<String>(
                   value: _simpleValue3,
-                  child: new Text('Context menu item three')
+                  child: const Text('Context menu item three')
                 ),
               ]
             )
@@ -114,7 +114,7 @@
           // a menu whose items have text labels and icons and a divider
           // That separates the first three items from the last one.
           new ListTile(
-            title: new Text('An item with a sectioned menu'),
+            title: const Text('An item with a sectioned menu'),
             trailing: new PopupMenuButton<String>(
               padding: EdgeInsets.zero,
               onSelected: showMenuSelection,
@@ -122,30 +122,30 @@
                 new PopupMenuItem<String>(
                   value: 'Preview',
                   child: new ListTile(
-                    leading: new Icon(Icons.visibility),
-                    title: new Text('Preview')
+                    leading: const Icon(Icons.visibility),
+                    title: const Text('Preview')
                   )
                 ),
                 new PopupMenuItem<String>(
                   value: 'Share',
                   child: new ListTile(
-                    leading: new Icon(Icons.person_add),
-                    title: new Text('Share')
+                    leading: const Icon(Icons.person_add),
+                    title: const Text('Share')
                   )
                 ),
                 new PopupMenuItem<String>(
                   value: 'Get Link',
                   child: new ListTile(
-                    leading: new Icon(Icons.link),
-                    title: new Text('Get link')
+                    leading: const Icon(Icons.link),
+                    title: const Text('Get link')
                   )
                 ),
                 new PopupMenuDivider(), // ignore: list_element_type_not_assignable, https://github.com/flutter/flutter/issues/5771
                 new PopupMenuItem<String>(
                   value: 'Remove',
                   child: new ListTile(
-                    leading: new Icon(Icons.delete),
-                    title: new Text('Remove')
+                    leading: const Icon(Icons.delete),
+                    title: const Text('Remove')
                   )
                 )
               ]
@@ -159,7 +159,7 @@
             initialValue: _simpleValue,
             onSelected: showMenuSelection,
             child: new ListTile(
-              title: new Text('An item with a simple menu'),
+              title: const Text('An item with a simple menu'),
               subtitle: new Text(_simpleValue)
             ),
             itemBuilder: (BuildContext context) => <PopupMenuItem<String>>[
@@ -180,7 +180,7 @@
           // Pressing the PopupMenuButton on the right of this item shows a menu
           // whose items have checked icons that reflect this app's state.
           new ListTile(
-            title: new Text('An item with a checklist menu'),
+            title: const Text('An item with a checklist menu'),
             trailing: new PopupMenuButton<String>(
               padding: EdgeInsets.zero,
               onSelected: showCheckedMenuSelections,
diff --git a/examples/flutter_gallery/lib/demo/material/modal_bottom_sheet_demo.dart b/examples/flutter_gallery/lib/demo/material/modal_bottom_sheet_demo.dart
index c0eee71..ec1540a 100644
--- a/examples/flutter_gallery/lib/demo/material/modal_bottom_sheet_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/modal_bottom_sheet_demo.dart
@@ -10,10 +10,10 @@
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Modal bottom sheet')),
+      appBar: new AppBar(title: const Text('Modal bottom sheet')),
       body: new Center(
         child: new RaisedButton(
-          child: new Text('SHOW BOTTOM SHEET'),
+          child: const Text('SHOW BOTTOM SHEET'),
           onPressed: () {
             showModalBottomSheet<Null>(context: context, builder: (BuildContext context) {
               return new Container(
diff --git a/examples/flutter_gallery/lib/demo/material/overscroll_demo.dart b/examples/flutter_gallery/lib/demo/material/overscroll_demo.dart
index 21ff0a7..d1cde79 100644
--- a/examples/flutter_gallery/lib/demo/material/overscroll_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/overscroll_demo.dart
@@ -29,7 +29,7 @@
     new Timer(const Duration(seconds: 3), () { completer.complete(null); });
     return completer.future.then((_) {
        _scaffoldKey.currentState?.showSnackBar(new SnackBar(
-         content: new Text("Refresh complete"),
+         content: const Text("Refresh complete"),
          action: new SnackBarAction(
            label: 'RETRY',
            onPressed: () {
@@ -45,10 +45,10 @@
     return new Scaffold(
       key: _scaffoldKey,
       appBar: new AppBar(
-        title: new Text('Pull to refresh'),
+        title: const Text('Pull to refresh'),
         actions: <Widget>[
           new IconButton(
-            icon: new Icon(Icons.refresh),
+            icon: const Icon(Icons.refresh),
             tooltip: 'Refresh',
             onPressed: () {
               _refreshIndicatorKey.currentState.show();
@@ -68,7 +68,7 @@
               isThreeLine: true,
               leading: new CircleAvatar(child: new Text(item)),
               title: new Text('This item represents $item.'),
-              subtitle: new Text('Even more additional list item information appears on line three.'),
+              subtitle: const Text('Even more additional list item information appears on line three.'),
             );
           },
         ),
diff --git a/examples/flutter_gallery/lib/demo/material/page_selector_demo.dart b/examples/flutter_gallery/lib/demo/material/page_selector_demo.dart
index daf23ec..a6fd74c 100644
--- a/examples/flutter_gallery/lib/demo/material/page_selector_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/page_selector_demo.dart
@@ -26,14 +26,14 @@
           child: new Row(
             children: <Widget>[
               new IconButton(
-                icon: new Icon(Icons.chevron_left),
+                icon: const Icon(Icons.chevron_left),
                 color: color,
                 onPressed: () { _handleArrowButtonPress(context, -1); },
                 tooltip: 'Page back'
               ),
               new TabPageSelector(controller: controller),
               new IconButton(
-                icon: new Icon(Icons.chevron_right),
+                icon: const Icon(Icons.chevron_right),
                 color: color,
                 onPressed: () { _handleArrowButtonPress(context, 1); },
                 tooltip: 'Page forward'
@@ -76,7 +76,7 @@
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Page selector')),
+      appBar: new AppBar(title: const Text('Page selector')),
       body: new DefaultTabController(
         length: icons.length,
         child: new _PageSelector(icons: icons),
diff --git a/examples/flutter_gallery/lib/demo/material/persistent_bottom_sheet_demo.dart b/examples/flutter_gallery/lib/demo/material/persistent_bottom_sheet_demo.dart
index 53bca99..1f2d553 100644
--- a/examples/flutter_gallery/lib/demo/material/persistent_bottom_sheet_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/persistent_bottom_sheet_demo.dart
@@ -57,11 +57,11 @@
     showDialog<Null>(
       context: context,
       child: new AlertDialog(
-        content: new Text('You tapped the floating action button.'),
+        content: const Text('You tapped the floating action button.'),
         actions: <Widget>[
           new FlatButton(
             onPressed: () { Navigator.pop(context); },
-            child: new Text('OK')
+            child: const Text('OK')
           )
         ]
       )
@@ -72,16 +72,16 @@
   Widget build(BuildContext context) {
     return new Scaffold(
       key: _scaffoldKey,
-      appBar: new AppBar(title: new Text('Persistent bottom sheet')),
+      appBar: new AppBar(title: const Text('Persistent bottom sheet')),
       floatingActionButton: new FloatingActionButton(
         onPressed: _showMessage,
         backgroundColor: Colors.redAccent,
-        child: new Icon(Icons.add)
+        child: const Icon(Icons.add)
       ),
       body: new Center(
         child: new RaisedButton(
           onPressed: _showBottomSheetCallback,
-          child: new Text('SHOW BOTTOM SHEET')
+          child: const Text('SHOW BOTTOM SHEET')
         )
       )
     );
diff --git a/examples/flutter_gallery/lib/demo/material/progress_indicator_demo.dart b/examples/flutter_gallery/lib/demo/material/progress_indicator_demo.dart
index d514d6d..4b55eed 100644
--- a/examples/flutter_gallery/lib/demo/material/progress_indicator_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/progress_indicator_demo.dart
@@ -25,7 +25,7 @@
 
     _animation = new CurvedAnimation(
       parent: _controller,
-      curve: new Interval(0.0, 0.9, curve: Curves.fastOutSlowIn),
+      curve: const Interval(0.0, 0.9, curve: Curves.fastOutSlowIn),
       reverseCurve: Curves.fastOutSlowIn
     )..addStatusListener((AnimationStatus status) {
       if (status == AnimationStatus.dismissed)
@@ -99,7 +99,7 @@
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Progress indicators')),
+      appBar: new AppBar(title: const Text('Progress indicators')),
       body: new Center(
         child: new SingleChildScrollView(
           child: new DefaultTextStyle(
diff --git a/examples/flutter_gallery/lib/demo/material/scrollable_tabs_demo.dart b/examples/flutter_gallery/lib/demo/material/scrollable_tabs_demo.dart
index 2e4901c..54213d6 100644
--- a/examples/flutter_gallery/lib/demo/material/scrollable_tabs_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/scrollable_tabs_demo.dart
@@ -59,22 +59,22 @@
     final Color iconColor = Theme.of(context).accentColor;
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Scrollable tabs'),
+        title: const Text('Scrollable tabs'),
         actions: <Widget>[
           new PopupMenuButton<TabsDemoStyle>(
             onSelected: changeDemoStyle,
             itemBuilder: (BuildContext context) => <PopupMenuItem<TabsDemoStyle>>[
               new PopupMenuItem<TabsDemoStyle>(
                 value: TabsDemoStyle.iconsAndText,
-                child: new Text('Icons and text')
+                child: const Text('Icons and text')
               ),
               new PopupMenuItem<TabsDemoStyle>(
                 value: TabsDemoStyle.iconsOnly,
-                child: new Text('Icons only')
+                child: const Text('Icons only')
               ),
               new PopupMenuItem<TabsDemoStyle>(
                 value: TabsDemoStyle.textOnly,
-                child: new Text('Text only')
+                child: const Text('Text only')
               ),
             ],
           ),
diff --git a/examples/flutter_gallery/lib/demo/material/slider_demo.dart b/examples/flutter_gallery/lib/demo/material/slider_demo.dart
index 41d142a..acd8d00 100644
--- a/examples/flutter_gallery/lib/demo/material/slider_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/slider_demo.dart
@@ -18,7 +18,7 @@
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Sliders')),
+      appBar: new AppBar(title: const Text('Sliders')),
       body: new Center(
         child: new Column(
           mainAxisAlignment: MainAxisAlignment.spaceAround,
@@ -37,14 +37,14 @@
                     });
                   }
                 ),
-                new Text('Continuous'),
+                const Text('Continuous'),
               ]
             ),
             new Column(
               mainAxisSize: MainAxisSize.min,
               children: <Widget> [
                 new Slider(value: 0.25, thumbOpenAtMin: true, onChanged: null),
-                new Text('Disabled'),
+                const Text('Disabled'),
               ]
             ),
             new Column(
@@ -63,7 +63,7 @@
                     });
                   }
                 ),
-                new Text('Discrete'),
+                const Text('Discrete'),
               ],
             ),
           ],
diff --git a/examples/flutter_gallery/lib/demo/material/snack_bar_demo.dart b/examples/flutter_gallery/lib/demo/material/snack_bar_demo.dart
index e78d255..b843b80 100644
--- a/examples/flutter_gallery/lib/demo/material/snack_bar_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/snack_bar_demo.dart
@@ -32,11 +32,11 @@
     return new ListView(
       padding: const EdgeInsets.all(24.0),
       children: <Widget>[
-        new Text(_text1),
-        new Text(_text2),
+        const Text(_text1),
+        const Text(_text2),
         new Center(
           child: new RaisedButton(
-            child: new Text('SHOW A SNACKBAR'),
+            child: const Text('SHOW A SNACKBAR'),
             onPressed: () {
               final int thisSnackBarIndex = _snackBarIndex++;
               Scaffold.of(context).showSnackBar(new SnackBar(
@@ -53,7 +53,7 @@
             }
           )
         ),
-        new Text(_text3),
+        const Text(_text3),
       ]
       .map((Widget child) {
         return new Container(
@@ -69,7 +69,7 @@
   Widget build(BuildContext context) {
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Snackbar')
+        title: const Text('Snackbar')
       ),
       body: new Builder(
         // Create an inner BuildContext so that the snackBar onPressed methods
diff --git a/examples/flutter_gallery/lib/demo/material/tabs_demo.dart b/examples/flutter_gallery/lib/demo/material/tabs_demo.dart
index f229953..d93c7ca 100644
--- a/examples/flutter_gallery/lib/demo/material/tabs_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/tabs_demo.dart
@@ -120,7 +120,7 @@
       length: _allPages.length,
       child: new Scaffold(
         appBar: new AppBar(
-          title: new Text('Tabs and scrolling'),
+          title: const Text('Tabs and scrolling'),
           bottom: new TabBar(
             tabs: _allPages.keys.map((_Page page) => new Tab(text: page.label)).toList(),
           ),
diff --git a/examples/flutter_gallery/lib/demo/material/tabs_fab_demo.dart b/examples/flutter_gallery/lib/demo/material/tabs_fab_demo.dart
index e9575e9..018be79 100644
--- a/examples/flutter_gallery/lib/demo/material/tabs_fab_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/tabs_fab_demo.dart
@@ -106,7 +106,7 @@
     return new Scaffold(
       key: _scaffoldKey,
       appBar: new AppBar(
-        title: new Text('FAB per tab'),
+        title: const Text('FAB per tab'),
         bottom: new TabBar(
           controller: _controller,
           tabs: _allPages.map((_Page page) => new Tab(text: page.label.toUpperCase())).toList(),
diff --git a/examples/flutter_gallery/lib/demo/material/text_form_field_demo.dart b/examples/flutter_gallery/lib/demo/material/text_form_field_demo.dart
index 2b0e5cd..bac851a 100644
--- a/examples/flutter_gallery/lib/demo/material/text_form_field_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/text_form_field_demo.dart
@@ -83,15 +83,15 @@
     return await showDialog<bool>(
       context: context,
       child: new AlertDialog(
-        title: new Text('This form has errors'),
-        content: new Text('Really leave this form?'),
+        title: const Text('This form has errors'),
+        content: const Text('Really leave this form?'),
         actions: <Widget> [
           new FlatButton(
-            child: new Text('YES'),
+            child: const Text('YES'),
             onPressed: () { Navigator.of(context).pop(true); },
           ),
           new FlatButton(
-            child: new Text('NO'),
+            child: const Text('NO'),
             onPressed: () { Navigator.of(context).pop(false); },
           ),
         ],
@@ -104,7 +104,7 @@
     return new Scaffold(
       key: _scaffoldKey,
       appBar: new AppBar(
-        title: new Text('Text fields'),
+        title: const Text('Text fields'),
       ),
       body: new Form(
         key: _formKey,
@@ -170,7 +170,7 @@
               padding: const EdgeInsets.all(20.0),
               alignment: const FractionalOffset(0.5, 0.5),
               child: new RaisedButton(
-                child: new Text('SUBMIT'),
+                child: const Text('SUBMIT'),
                 onPressed: _handleSubmitted,
               ),
             ),
diff --git a/examples/flutter_gallery/lib/demo/material/tooltip_demo.dart b/examples/flutter_gallery/lib/demo/material/tooltip_demo.dart
index 84c3c0d..a6d025d 100644
--- a/examples/flutter_gallery/lib/demo/material/tooltip_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/tooltip_demo.dart
@@ -18,7 +18,7 @@
     final ThemeData theme = Theme.of(context);
     return new Scaffold(
       appBar: new AppBar(
-        title: new Text('Tooltips')
+        title: const Text('Tooltips')
       ),
       body: new Builder(
         builder: (BuildContext context) {
@@ -42,12 +42,12 @@
               new Center(
                 child: new IconButton(
                   iconSize: 48.0,
-                  icon: new Icon(Icons.call),
+                  icon: const Icon(Icons.call),
                   color: theme.iconTheme.color,
                   tooltip: 'Place a phone call',
                   onPressed: () {
                     Scaffold.of(context).showSnackBar(new SnackBar(
-                       content: new Text('That was an ordinary tap.')
+                       content: const Text('That was an ordinary tap.')
                     ));
                   }
                 )
diff --git a/examples/flutter_gallery/lib/demo/material/two_level_list_demo.dart b/examples/flutter_gallery/lib/demo/material/two_level_list_demo.dart
index 2307926..d152173 100644
--- a/examples/flutter_gallery/lib/demo/material/two_level_list_demo.dart
+++ b/examples/flutter_gallery/lib/demo/material/two_level_list_demo.dart
@@ -10,23 +10,23 @@
   @override
   Widget build(BuildContext context) {
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Expand/collapse list control')),
+      appBar: new AppBar(title: const Text('Expand/collapse list control')),
       body: new TwoLevelList(
         type: MaterialListType.oneLine,
         children: <Widget>[
-          new TwoLevelListItem(title: new Text('Top')),
+          new TwoLevelListItem(title: const Text('Top')),
           new TwoLevelSublist(
-             title: new Text('Sublist'),
+             title: const Text('Sublist'),
              backgroundColor: Theme.of(context).accentColor.withOpacity(0.025),
              children: <Widget>[
-               new TwoLevelListItem(title: new Text('One')),
-               new TwoLevelListItem(title: new Text('Two')),
+               new TwoLevelListItem(title: const Text('One')),
+               new TwoLevelListItem(title: const Text('Two')),
                // https://en.wikipedia.org/wiki/Free_Four
-               new TwoLevelListItem(title: new Text('Free')),
-               new TwoLevelListItem(title: new Text('Four'))
+               new TwoLevelListItem(title: const Text('Free')),
+               new TwoLevelListItem(title: const Text('Four'))
              ]
           ),
-           new TwoLevelListItem(title: new Text('Bottom'))
+           new TwoLevelListItem(title: const Text('Bottom'))
         ]
       )
     );
diff --git a/examples/flutter_gallery/lib/demo/pesto_demo.dart b/examples/flutter_gallery/lib/demo/pesto_demo.dart
index b0cb6f4..f6ce4db 100644
--- a/examples/flutter_gallery/lib/demo/pesto_demo.dart
+++ b/examples/flutter_gallery/lib/demo/pesto_demo.dart
@@ -82,10 +82,10 @@
       child: new Scaffold(
         key: scaffoldKey,
         floatingActionButton: new FloatingActionButton(
-          child: new Icon(Icons.edit),
+          child: const Icon(Icons.edit),
           onPressed: () {
             scaffoldKey.currentState.showSnackBar(new SnackBar(
-              content: new Text('Not supported.'),
+              content: const Text('Not supported.'),
             ));
           },
         ),
@@ -105,11 +105,11 @@
       expandedHeight: _kAppBarHeight,
       actions: <Widget>[
         new IconButton(
-          icon: new Icon(Icons.search),
+          icon: const Icon(Icons.search),
           tooltip: 'Search',
           onPressed: () {
             scaffoldKey.currentState.showSnackBar(new SnackBar(
-              content: new Text('Not supported.'),
+              content: const Text('Not supported.'),
             ));
           },
         ),
diff --git a/examples/flutter_gallery/lib/demo/shrine/shrine_order.dart b/examples/flutter_gallery/lib/demo/shrine/shrine_order.dart
index c7f5a1f..a53d702 100644
--- a/examples/flutter_gallery/lib/demo/shrine/shrine_order.dart
+++ b/examples/flutter_gallery/lib/demo/shrine/shrine_order.dart
@@ -181,7 +181,7 @@
               ),
               new LayoutId(
                 id: _HeadingLayout.icon,
-                child: new Icon(
+                child: const Icon(
                   Icons.info_outline,
                   size: 24.0,
                   color: const Color(0xFFFFE0E0),
@@ -275,7 +275,7 @@
           );
         },
         backgroundColor: const Color(0xFF16F0F0),
-        child: new Icon(
+        child: const Icon(
           Icons.add_shopping_cart,
           color: Colors.black,
         ),
diff --git a/examples/flutter_gallery/lib/demo/shrine/shrine_page.dart b/examples/flutter_gallery/lib/demo/shrine/shrine_page.dart
index be90c77..467bf1f 100644
--- a/examples/flutter_gallery/lib/demo/shrine/shrine_page.dart
+++ b/examples/flutter_gallery/lib/demo/shrine/shrine_page.dart
@@ -54,9 +54,9 @@
   void _showShoppingCart() {
     showModalBottomSheet<Null>(context: context, builder: (BuildContext context) {
       if (config.shoppingCart.isEmpty) {
-        return new Padding(
+        return const Padding(
           padding: const EdgeInsets.all(24.0),
-          child: new Text('The shopping cart is empty')
+          child: const Text('The shopping cart is empty')
         );
       }
       return new ListView(
@@ -82,7 +82,7 @@
 
   void _emptyCart() {
     config.shoppingCart.clear();
-    config.scaffoldKey.currentState.showSnackBar(new SnackBar(content: new Text('Shopping cart is empty')));
+    config.scaffoldKey.currentState.showSnackBar(new SnackBar(content: const Text('Shopping cart is empty')));
   }
 
   @override
@@ -107,7 +107,7 @@
         ),
         actions: <Widget>[
           new IconButton(
-            icon: new Icon(Icons.shopping_cart),
+            icon: const Icon(Icons.shopping_cart),
             tooltip: 'Shopping cart',
             onPressed: _showShoppingCart
           ),
@@ -115,15 +115,15 @@
             itemBuilder: (BuildContext context) => <PopupMenuItem<ShrineAction>>[
               new PopupMenuItem<ShrineAction>(
                 value: ShrineAction.sortByPrice,
-                child: new Text('Sort by price')
+                child: const Text('Sort by price')
               ),
               new PopupMenuItem<ShrineAction>(
                 value: ShrineAction.sortByProduct,
-                child: new Text('Sort by product')
+                child: const Text('Sort by product')
               ),
               new PopupMenuItem<ShrineAction>(
                 value: ShrineAction.emptyCart,
-                child: new Text('Empty shopping cart')
+                child: const Text('Empty shopping cart')
               )
             ],
             onSelected: (ShrineAction action) {
diff --git a/examples/flutter_gallery/lib/demo/typography_demo.dart b/examples/flutter_gallery/lib/demo/typography_demo.dart
index 33b947c..da6e34f 100644
--- a/examples/flutter_gallery/lib/demo/typography_demo.dart
+++ b/examples/flutter_gallery/lib/demo/typography_demo.dart
@@ -71,7 +71,7 @@
     }
 
     return new Scaffold(
-      appBar: new AppBar(title: new Text('Typography')),
+      appBar: new AppBar(title: const Text('Typography')),
       body: new ListView(children: styleItems)
     );
   }
diff --git a/examples/flutter_gallery/lib/gallery/demo.dart b/examples/flutter_gallery/lib/gallery/demo.dart
index 047b4c7..9099c14 100644
--- a/examples/flutter_gallery/lib/gallery/demo.dart
+++ b/examples/flutter_gallery/lib/gallery/demo.dart
@@ -61,7 +61,7 @@
             new Builder(
               builder: (BuildContext context) {
                 return new IconButton(
-                  icon: new Icon(Icons.description),
+                  icon: const Icon(Icons.description),
                   tooltip: 'Show example code',
                   onPressed: () {
                     _showExampleCode(context);
@@ -150,10 +150,10 @@
     return new Scaffold(
       appBar: new AppBar(
         leading: new IconButton(
-          icon: new Icon(Icons.clear),
+          icon: const Icon(Icons.clear),
           onPressed: () { Navigator.pop(context); }
         ),
-        title: new Text('Example code')
+        title: const Text('Example code')
       ),
       body: body
     );
diff --git a/examples/flutter_gallery/lib/gallery/drawer.dart b/examples/flutter_gallery/lib/gallery/drawer.dart
index 098b840..0e2d138 100644
--- a/examples/flutter_gallery/lib/gallery/drawer.dart
+++ b/examples/flutter_gallery/lib/gallery/drawer.dart
@@ -127,8 +127,8 @@
     final TextStyle linkStyle = themeData.textTheme.body2.copyWith(color: themeData.accentColor);
 
     final Widget lightThemeItem = new ListTile(
-      leading: new Icon(Icons.brightness_5),
-      title: new Text('Light'),
+      leading: const Icon(Icons.brightness_5),
+      title: const Text('Light'),
       trailing: new Radio<bool>(
         value: true,
         groupValue: useLightTheme,
@@ -141,8 +141,8 @@
     );
 
     final Widget darkThemeItem = new ListTile(
-      leading: new Icon(Icons.brightness_7),
-      title: new Text('Dark'),
+      leading: const Icon(Icons.brightness_7),
+      title: const Text('Dark'),
       trailing: new Radio<bool>(
         value: false,
         groupValue: useLightTheme,
@@ -157,7 +157,7 @@
     final Widget mountainViewItem = new ListTile(
       // on iOS, we don't want to show an Android phone icon
       leading: new Icon(defaultTargetPlatform == TargetPlatform.iOS ? Icons.star : Icons.phone_android),
-      title: new Text('Android'),
+      title: const Text('Android'),
       trailing: new Radio<TargetPlatform>(
         value: TargetPlatform.android,
         groupValue: Theme.of(context).platform,
@@ -172,7 +172,7 @@
     final Widget cupertinoItem = new ListTile(
       // on iOS, we don't want to show the iPhone icon
       leading: new Icon(defaultTargetPlatform == TargetPlatform.iOS ? Icons.star_border : Icons.phone_iphone),
-      title: new Text('iOS'),
+      title: const Text('iOS'),
       trailing: new Radio<TargetPlatform>(
         value: TargetPlatform.iOS,
         groupValue: Theme.of(context).platform,
@@ -185,8 +185,8 @@
     );
 
     final Widget animateSlowlyItem = new ListTile(
-      leading: new Icon(Icons.hourglass_empty),
-      title: new Text('Animate Slowly'),
+      leading: const Icon(Icons.hourglass_empty),
+      title: const Text('Animate Slowly'),
       trailing: new Checkbox(
         value: timeDilation != 1.0,
         onChanged: (bool value) {
@@ -200,8 +200,8 @@
     );
 
     final Widget sendFeedbackItem = new ListTile(
-      leading: new Icon(Icons.report),
-      title: new Text('Send feedback'),
+      leading: const Icon(Icons.report),
+      title: const Text('Send feedback'),
       onTap: onSendFeedback ?? () {
         UrlLauncher.launch('https://github.com/flutter/flutter/issues/new');
       },
@@ -266,8 +266,8 @@
 
     if (onShowPerformanceOverlayChanged != null) {
       allDrawerItems.insert(8, new ListTile(
-        leading: new Icon(Icons.assessment),
-        title: new Text('Performance Overlay'),
+        leading: const Icon(Icons.assessment),
+        title: const Text('Performance Overlay'),
         trailing: new Checkbox(
           value: showPerformanceOverlay,
           onChanged: (bool value) {
@@ -283,8 +283,8 @@
 
     if (onCheckerboardRasterCacheImagesChanged != null) {
       allDrawerItems.insert(8, new ListTile(
-        leading: new Icon(Icons.assessment),
-        title: new Text('Checkerboard Raster Cache Images'),
+        leading: const Icon(Icons.assessment),
+        title: const Text('Checkerboard Raster Cache Images'),
         trailing: new Checkbox(
           value: checkerboardRasterCacheImages,
           onChanged: (bool value) {
diff --git a/examples/flutter_gallery/lib/gallery/example_code.dart b/examples/flutter_gallery/lib/gallery/example_code.dart
index 42ec4f3..f594f61 100644
--- a/examples/flutter_gallery/lib/gallery/example_code.dart
+++ b/examples/flutter_gallery/lib/gallery/example_code.dart
@@ -16,7 +16,7 @@
 // START buttons_raised
 // Create a raised button.
 new RaisedButton(
-  child: new Text('BUTTON TITLE'),
+  child: const Text('BUTTON TITLE'),
   onPressed: () {
     // Perform some action
   }
@@ -26,7 +26,7 @@
 // Buttons are disabled when onPressed isn't
 // specified or is null.
 new RaisedButton(
-  child: new Text('BUTTON TITLE'),
+  child: const Text('BUTTON TITLE'),
   onPressed: null
 );
 // END
@@ -35,7 +35,7 @@
 // START buttons_flat
 // Create a flat button.
 new FlatButton(
-  child: new Text('BUTTON TITLE'),
+  child: const Text('BUTTON TITLE'),
   onPressed: () {
     // Perform some action
   }
@@ -45,7 +45,7 @@
 // Buttons are disabled when onPressed isn't
 // specified or is null.
 new FlatButton(
-  child: new Text('BUTTON TITLE'),
+  child: const Text('BUTTON TITLE'),
   onPressed: null
 );
 // END
@@ -83,7 +83,7 @@
 
 // Toggleable icon button.
 new IconButton(
-  icon: new Icon(Icons.thumb_up),
+  icon: const Icon(Icons.thumb_up),
   onPressed: () {
     setState(() => value = !value);
   },
@@ -96,10 +96,10 @@
 // Floating action button in Scaffold.
 new Scaffold(
   appBar: new AppBar(
-    title: new Text('Demo')
+    title: const Text('Demo')
   ),
-  floatingActionButton: new FloatingActionButton(
-    child: new Icon(Icons.add),
+  floatingActionButton: const FloatingActionButton(
+    child: const Icon(Icons.add),
     onPressed: null
   )
 );
diff --git a/examples/flutter_gallery/lib/gallery/home.dart b/examples/flutter_gallery/lib/gallery/home.dart
index 6177529..adeace8 100644
--- a/examples/flutter_gallery/lib/gallery/home.dart
+++ b/examples/flutter_gallery/lib/gallery/home.dart
@@ -170,7 +170,7 @@
             pinned: true,
             expandedHeight: _kFlexibleSpaceMaxHeight,
             flexibleSpace: new FlexibleSpaceBar(
-              title: new Text('Flutter Gallery'),
+              title: const Text('Flutter Gallery'),
               // TODO(abarth): Wire up to the parallax in a way that doesn't pop during hero transition.
               background: new _AppBarBackground(animation: kAlwaysDismissedAnimation),
             ),
@@ -194,7 +194,7 @@
           home,
           new FadeTransition(
             opacity: new CurvedAnimation(parent: _controller, curve: Curves.easeInOut),
-            child: new Banner(
+            child: const Banner(
               message: 'PREVIEW',
               location: BannerLocation.topRight,
             )
diff --git a/examples/flutter_gallery/lib/gallery/updates.dart b/examples/flutter_gallery/lib/gallery/updates.dart
index e46c5b9..fcc110d 100644
--- a/examples/flutter_gallery/lib/gallery/updates.dart
+++ b/examples/flutter_gallery/lib/gallery/updates.dart
@@ -51,16 +51,16 @@
     final TextStyle dialogTextStyle =
         theme.textTheme.subhead.copyWith(color: theme.textTheme.caption.color);
     return new AlertDialog(
-      title: new Text('Update Flutter Gallery?'),
+      title: const Text('Update Flutter Gallery?'),
       content: new Text('A newer version is available.', style: dialogTextStyle),
       actions: <Widget>[
         new FlatButton(
-            child: new Text('NO THANKS'),
+            child: const Text('NO THANKS'),
             onPressed: () {
               Navigator.pop(context, false);
             }),
         new FlatButton(
-            child: new Text('UPDATE'),
+            child: const Text('UPDATE'),
             onPressed: () {
               Navigator.pop(context, true);
             }),