VM: Make use_osr an Isolate flag, similar to how we made use_field_guards.

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;
 import 'runtime_configuration.dart' show DartPrecompiledAdbRuntimeConfiguration;
@@ skipping 195 matching lines @@
   List<String> computeRuntimeArguments(
       RuntimeConfiguration runtimeConfiguration,
       String buildDir,
       TestInformation info,
       List<String> vmOptions,
       List<String> sharedOptions,
       List<String> originalArguments,
       CommandArtifact artifact) {
     List<String> args = [];
     if (useDFE) {
-      args.add('--dfe=utils/kernel-service/kernel-service.dart');
+      args.add('--dfe=${buildDir}/gen/kernel-service.dart.snapshot');
     }
     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');
     }
@@ skipping 684 matching lines @@
       RuntimeConfiguration runtimeConfiguration,
       String buildDir,
       TestInformation info,
       List<String> vmOptions,
       List<String> sharedOptions,
       List<String> originalArguments,
       CommandArtifact artifact) {
     return <String>[];
   }
 }