Make unit testing of the compiler work with the new isolate helper library.

sdk/lib/_internal/compiler/implementation/native_handler.dart

 // Copyright (c) 2012, 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 native;
 
 import 'dart:uri';
 import 'dart2jslib.dart' hide SourceString;
 import 'elements/elements.dart';
 import 'js_backend/js_backend.dart';
@@ skipping 16 matching lines @@
   static const JsArray = const SpecialType._('=List');
 }
 
 
 /**
  * This could be an abstract class but we use it as a stub for the dart_backend.
  */
 class NativeEnqueuer {
   /// Initial entry point to native enqueuer.
   void processNativeClasses(Collection<LibraryElement> libraries) {}
-  void processNativeClassesInLibrary(LibraryElement library) {}
 
   /// Notification of a main Enqueuer worklist element.  For methods, adds
   /// information from metadata attributes, and computes types instantiated due
   /// to calling the method.
   void registerElement(Element element) {}
 
   /// Notification of native field.  Adds information from metadata attributes.
   void handleFieldAnnotations(Element field) {}
 
   /// Computes types instantiated due to getting a native field.
@@ skipping 49 matching lines @@
 
   ClassElement _annotationCreatesClass;
   ClassElement _annotationReturnsClass;
   ClassElement _annotationJsNameClass;
 
   /// Subclasses of [NativeEnqueuerBase] are constructed by the backend.
   NativeEnqueuerBase(this.world, this.compiler, this.enableLiveTypeAnalysis);
 
   void processNativeClasses(Collection<LibraryElement> libraries) {
     libraries.forEach(processNativeClassesInLibrary);
+    processNativeClassesInLibrary(compiler.isolateHelperLibrary);
     if (!enableLiveTypeAnalysis) {
       nativeClasses.forEach((c) => enqueueClass(c, 'forced'));
       flushQueue();
     }
   }
 
   void processNativeClassesInLibrary(LibraryElement library) {
     // Use implementation to ensure the inclusion of injected members.
     library.implementation.forEachLocalMember((Element element) {
       if (element.isClass() && element.isNative()) {
@@ skipping 772 matching lines @@
         builder.add(new HForeign(
             new DartString.literal('${parameter.name.slowToString()} = #'),
             const LiteralDartString('void'),
             <HInstruction>[jsClosure]));
       }
     });
     LiteralString jsCode = nativeBody.asLiteralString();
     builder.push(new HForeign.statement(jsCode.dartString, <HInstruction>[]));
   }
 }