Add --hot-reload-rollback test mode

tools/testing/dart/compiler_configuration.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 library compiler_configuration;
 
 import 'dart:io' show Platform;
 
 import 'runtime_configuration.dart' show RuntimeConfiguration;
 
@@ skipping 36 matching lines @@
     // which can eventually completely replace the Map-based configuration
     // object.
     bool isDebug = configuration['mode'] == 'debug';
     bool isChecked = configuration['checked'];
     bool isHostChecked = configuration['host_checked'];
     bool useSdk = configuration['use_sdk'];
     bool isCsp = configuration['csp'];
     bool useCps = configuration['cps_ir'];
     bool useBlobs = configuration['use_blobs'];
     bool hotReload = configuration['hot_reload'];
+    bool hotReloadRollback = configuration['hot_reload_rollback'];
 
     switch (compiler) {
       case 'dart2analyzer':
         return new AnalyzerCompilerConfiguration(
             isDebug: isDebug,
             isChecked: isChecked,
             isHostChecked: isHostChecked,
             useSdk: useSdk);
       case 'dart2js':
         return new Dart2jsCompilerConfiguration(
@@ skipping 17 matching lines @@
             isChecked: isChecked,
             arch: configuration['arch'],
             useBlobs: useBlobs,
             isAndroid: configuration['system'] == 'android');
       case 'none':
         return new NoneCompilerConfiguration(
             isDebug: isDebug,
             isChecked: isChecked,
             isHostChecked: isHostChecked,
             useSdk: useSdk,
-            hotReload: hotReload);
+            hotReload: hotReload,
+            hotReloadRollback: hotReloadRollback);
       default:
         throw "Unknown compiler '$compiler'";
     }
   }
 
   CompilerConfiguration._subclass(
       {this.isDebug: false,
       this.isChecked: false,
       this.isHostChecked: false,
       this.useSdk: false});
@@ skipping 40 matching lines @@
       List<String> sharedOptions,
       List<String> originalArguments,
       CommandArtifact artifact) {
     return <String>[artifact.filename];
   }
 }
 
 /// The "none" compiler.
 class NoneCompilerConfiguration extends CompilerConfiguration {
   final bool hotReload;
+  final bool hotReloadRollback;
 
   NoneCompilerConfiguration(
       {bool isDebug, bool isChecked, bool isHostChecked, bool useSdk,
-       bool hotReload})
+       bool hotReload,
+       bool hotReloadRollback})
       : super._subclass(
             isDebug: isDebug,
             isChecked: isChecked,
             isHostChecked: isHostChecked,
             useSdk: useSdk),
-        this.hotReload = hotReload;
+        this.hotReload = hotReload,
+        this.hotReloadRollback = hotReloadRollback;
 
   bool get hasCompiler => false;
 
   List<String> computeRuntimeArguments(
       RuntimeConfiguration runtimeConfiguration,
       String buildDir,
       TestInformation info,
       List<String> vmOptions,
       List<String> sharedOptions,
       List<String> originalArguments,
       CommandArtifact artifact) {
     List<String> args = [];
     if (isChecked) {
       args.add('--enable_asserts');
       args.add('--enable_type_checks');
     }
     if (hotReload) {
       args.add('--hot-reload-test-mode');
+    } else if (hotReloadRollback) {
+      args.add('--hot-reload-rollback-test-mode');
     }
     return args
       ..addAll(vmOptions)
       ..addAll(sharedOptions)
       ..addAll(originalArguments);
   }
 }
 
 /// Common configuration for dart2js-based tools, such as, dart2js
 class Dart2xCompilerConfiguration extends CompilerConfiguration {
@@ skipping 455 matching lines @@
       RuntimeConfiguration runtimeConfiguration,
       String buildDir,
       TestInformation info,
       List<String> vmOptions,
       List<String> sharedOptions,
       List<String> originalArguments,
       CommandArtifact artifact) {
     return <String>[];
   }
 }