Merge pull request #2339 from sethladd/doc

move the link around for flutter doc homepage

packages/flutter/lib/src/animation/animation_controller.dart

diff --git a/packages/flutter/lib/src/animation/animation_controller.dart b/packages/flutter/lib/src/animation/animation_controller.dart
index e4c0b20..205ecd4 100644
--- a/packages/flutter/lib/src/animation/animation_controller.dart
+++ b/packages/flutter/lib/src/animation/animation_controller.dart
@@ -125,13 +125,17 @@
   }
 
   /// Starts running this animation forwards (towards the end).
-  Future forward() {
+  Future forward({ double from }) {
+    if (from != null)
+      value = from;
     _direction = _AnimationDirection.forward;
     return animateTo(upperBound);
   }
 
   /// Starts running this animation in reverse (towards the beginning).
-  Future reverse() {
+  Future reverse({ double from }) {
+    if (from != null)
+      value = from;
     _direction = _AnimationDirection.reverse;
     return animateTo(lowerBound);
   }

packages/flutter/lib/src/material/icon.dart

diff --git a/packages/flutter/lib/src/material/icon.dart b/packages/flutter/lib/src/material/icon.dart
index e3ed79d..d27572d 100644
--- a/packages/flutter/lib/src/material/icon.dart
+++ b/packages/flutter/lib/src/material/icon.dart
@@ -9,11 +9,24 @@
 import 'icon_theme.dart';
 import 'theme.dart';
 
+/// A material design icon.
+///
+/// Available icons are shown on this page:
+/// <https://design.google.com/icons/>
+///
+/// Icons are identified by their name (as given on that page), with
+/// spaces converted to underscores, from the [Icons] class. For
+/// example, the "alarm add" icon is [Icons.alarm_add].
+///
+/// To use this class, make sure you set `uses-material-design: true`
+/// in your project's `flutter.yaml` file. This ensures that the
+/// MaterialIcons font is included in your application. This font is
+/// used to display the icons.
 class Icon extends StatelessComponent {
   Icon({
     Key key,
-    this.size: 24.0,
     this.icon,
+    this.size: 24.0,
     this.color
   }) : super(key: key) {
     assert(size != null);
@@ -52,16 +65,19 @@
     if (iconAlpha != 255)
         iconColor = color.withAlpha((iconAlpha * color.opacity).round());
 
-    return new SizedBox(
-      width: size,
-      height: size,
-      child: new Center(
-        child: new Text(new String.fromCharCode(icon.codePoint),
-          style: new TextStyle(
-            inherit: false,
-            color: iconColor,
-            fontSize: size,
-            fontFamily: 'MaterialIcons'
+    return new ExcludeSemantics(
+      child: new SizedBox(
+        width: size,
+        height: size,
+        child: new Center(
+          child: new Text(
+            new String.fromCharCode(icon.codePoint),
+            style: new TextStyle(
+              inherit: false,
+              color: iconColor,
+              fontSize: size,
+              fontFamily: 'MaterialIcons'
+            )
           )
         )
       )

packages/flutter/test/animation/animation_controller_test.dart

diff --git a/packages/flutter/test/animation/animation_controller_test.dart b/packages/flutter/test/animation/animation_controller_test.dart
index f7f1903..b561bff 100644
--- a/packages/flutter/test/animation/animation_controller_test.dart
+++ b/packages/flutter/test/animation/animation_controller_test.dart
@@ -102,4 +102,32 @@
 
     controller.stop();
   });
+
+  test("Forward and reverse from values", () {
+    WidgetFlutterBinding.ensureInitialized();
+    AnimationController controller = new AnimationController(
+      duration: const Duration(milliseconds: 100)
+    );
+    List<double> valueLog = <double>[];
+    List<AnimationStatus> statusLog = <AnimationStatus>[];
+    controller
+      ..addStatusListener((AnimationStatus status) {
+        statusLog.add(status);
+      })
+      ..addListener(() {
+        valueLog.add(controller.value);
+      });
+
+    controller.reverse(from: 0.2);
+    expect(statusLog, equals([ AnimationStatus.reverse ]));
+    expect(valueLog, equals([ 0.2 ]));
+    expect(controller.value, equals(0.2));
+    statusLog.clear();
+    valueLog.clear();
+
+    controller.forward(from: 0.0);
+    expect(statusLog, equals([ AnimationStatus.dismissed, AnimationStatus.forward ]));
+    expect(valueLog, equals([ 0.0 ]));
+    expect(controller.value, equals(0.0));
+  });
 }