cc: Implement shared worker contexts. (v1)

cc/test/test_context_provider.h

Index: cc/test/test_context_provider.h
diff --git a/cc/test/test_context_provider.h b/cc/test/test_context_provider.h
index 82b3e612d681344d71d0dbf603f51dcfc8f437a7..598e2ebcc1121f6795a5f98ed687b3b0863e46ea 100644
--- a/cc/test/test_context_provider.h
+++ b/cc/test/test_context_provider.h
@@ -25,6 +25,9 @@ class TestContextProvider : public ContextProvider {
     CreateCallback;
 
   static scoped_refptr<TestContextProvider> Create();
+  // Creates a worker context provider that can be used on any thread. This is
+  // equivalent to: Create(); BindToCurrentThread(); SetupLock().
+  static scoped_refptr<TestContextProvider> CreateWorker();
   static scoped_refptr<TestContextProvider> Create(
       scoped_ptr<TestWebGraphicsContext3D> context);
 
@@ -43,6 +46,7 @@ class TestContextProvider : public ContextProvider {
   void SetLostContextCallback(const LostContextCallback& cb) override;
   void SetMemoryPolicyChangedCallback(
       const MemoryPolicyChangedCallback& cb) override;
+  bool HasBeenDestroyed() override;
 
   TestWebGraphicsContext3D* TestContext3d();