Friendlier flutter tool messages for dynamic mode (#26378)

diff --git a/packages/flutter_tools/lib/src/build_info.dart b/packages/flutter_tools/lib/src/build_info.dart
index f4d16db..7e4152a 100644
--- a/packages/flutter_tools/lib/src/build_info.dart
+++ b/packages/flutter_tools/lib/src/build_info.dart

@@ -119,6 +119,7 @@
   bool get supportsEmulator => isEmulatorBuildMode(mode);
   bool get supportsSimulator => isEmulatorBuildMode(mode);
   String get modeName => getModeName(mode);
+  String get friendlyModeName => getFriendlyModeName(mode);
 
   BuildInfo withTargetPlatform(TargetPlatform targetPlatform) =>
       BuildInfo(mode, flavor,
@@ -142,6 +143,10 @@
 
 String getModeName(BuildMode mode) => getEnumName(mode);
 
+String getFriendlyModeName(BuildMode mode) {
+  return snakeCase(getModeName(mode)).replaceAll('_', ' ');
+}
+
 // Returns true if the selected build mode uses ahead-of-time compilation.
 bool isAotBuildMode(BuildMode mode) {
   return mode == BuildMode.profile || mode == BuildMode.release;

diff --git a/packages/flutter_tools/lib/src/bundle.dart b/packages/flutter_tools/lib/src/bundle.dart
index 57b2c32..e90ce9b 100644
--- a/packages/flutter_tools/lib/src/bundle.dart
+++ b/packages/flutter_tools/lib/src/bundle.dart

@@ -85,7 +85,7 @@
 
     } else if (!fs.file(compilationTraceFilePath).existsSync()) {
       // Be forgiving if compilation trace file is missing.
-      printError('Warning: Ignoring missing compilation training file $compilationTraceFilePath.');
+      printStatus('No compilation trace available. To optimize performance, consider using --train.');
       final File tmp = fs.systemTempDirectory.childFile('flutterEmptyCompilationTrace.txt');
       compilationTraceFilePath = (tmp..createSync(recursive: true)).path;
 

diff --git a/packages/flutter_tools/lib/src/commands/build_aot.dart b/packages/flutter_tools/lib/src/commands/build_aot.dart
index d7ad96e..e7d40f7 100644
--- a/packages/flutter_tools/lib/src/commands/build_aot.dart
+++ b/packages/flutter_tools/lib/src/commands/build_aot.dart

@@ -70,7 +70,7 @@
     if (!argResults['quiet']) {
       final String typeName = artifacts.getEngineType(platform, buildMode);
       status = logger.startProgress(
-        'Building AOT snapshot in ${getModeName(getBuildMode())} mode ($typeName)...',
+        'Building AOT snapshot in ${getFriendlyModeName(getBuildMode())} mode ($typeName)...',
         expectSlowOperation: true,
       );
     }

diff --git a/packages/flutter_tools/lib/src/commands/build_ios.dart b/packages/flutter_tools/lib/src/commands/build_ios.dart
index e34c5eb..539eb76 100644
--- a/packages/flutter_tools/lib/src/commands/build_ios.dart
+++ b/packages/flutter_tools/lib/src/commands/build_ios.dart

@@ -70,7 +70,7 @@
     }
     final BuildInfo buildInfo = getBuildInfo();
     if (forSimulator && !buildInfo.supportsSimulator)
-      throwToolExit('${toTitleCase(buildInfo.modeName)} mode is not supported for simulators.');
+      throwToolExit('${toTitleCase(buildInfo.friendlyModeName)} mode is not supported for simulators.');
 
     final String logTarget = forSimulator ? 'simulator' : 'device';
 

diff --git a/packages/flutter_tools/lib/src/commands/daemon.dart b/packages/flutter_tools/lib/src/commands/daemon.dart
index 30b5d70..55f331f 100644
--- a/packages/flutter_tools/lib/src/commands/daemon.dart
+++ b/packages/flutter_tools/lib/src/commands/daemon.dart

@@ -342,7 +342,7 @@
     String isolateFilter,
   }) async {
     if (await device.isLocalEmulator && !options.buildInfo.supportsEmulator) {
-      throw '${toTitleCase(options.buildInfo.modeName)} mode is not supported for emulators.';
+      throw '${toTitleCase(options.buildInfo.friendlyModeName)} mode is not supported for emulators.';
     }
 
     // We change the current working directory for the duration of the `start` command.

diff --git a/packages/flutter_tools/lib/src/commands/run.dart b/packages/flutter_tools/lib/src/commands/run.dart
index 8964018..f68518a 100644
--- a/packages/flutter_tools/lib/src/commands/run.dart
+++ b/packages/flutter_tools/lib/src/commands/run.dart

@@ -303,7 +303,7 @@
         }
 
         if (!isEmulatorBuildMode(getBuildMode())) {
-          throwToolExit('${toTitleCase(getModeName(getBuildMode()))} mode is not supported for emulators.');
+          throwToolExit('${toTitleCase(getFriendlyModeName(getBuildMode()))} mode is not supported for emulators.');
         }
       }
     }

diff --git a/packages/flutter_tools/lib/src/resident_runner.dart b/packages/flutter_tools/lib/src/resident_runner.dart
index 4bd5dd4..50eb8ff 100644
--- a/packages/flutter_tools/lib/src/resident_runner.dart
+++ b/packages/flutter_tools/lib/src/resident_runner.dart

@@ -265,7 +265,7 @@
     bool shouldBuild,
   }) async {
     final bool prebuiltMode = hotRunner.applicationBinary != null;
-    final String modeName = hotRunner.debuggingOptions.buildInfo.modeName;
+    final String modeName = hotRunner.debuggingOptions.buildInfo.friendlyModeName;
     printStatus('Launching ${getDisplayPath(hotRunner.mainPath)} on ${device.name} in $modeName mode...');
 
     final TargetPlatform targetPlatform = await device.targetPlatform;
@@ -324,7 +324,7 @@
       applicationBinary: coldRunner.applicationBinary
     );
 
-    final String modeName = coldRunner.debuggingOptions.buildInfo.modeName;
+    final String modeName = coldRunner.debuggingOptions.buildInfo.friendlyModeName;
     final bool prebuiltMode = coldRunner.applicationBinary != null;
     if (coldRunner.mainPath == null) {
       assert(prebuiltMode);