Defer compositor context creation to the thread.

cc/output/renderer_unittest.cc

Index: cc/output/renderer_unittest.cc
diff --git a/cc/output/renderer_unittest.cc b/cc/output/renderer_unittest.cc
index 67d13caf40a7f6af65e2308488ea2268fc4c30d1..45955ecca3131ffc0233b6365ab01deeaee91f30 100644
--- a/cc/output/renderer_unittest.cc
+++ b/cc/output/renderer_unittest.cc
@@ -18,34 +18,40 @@ namespace {
 
 class TestOutputSurface : public OutputSurface {
  public:
-  explicit TestOutputSurface(scoped_refptr<ContextProvider> context_provider);
-  ~TestOutputSurface() override;
-
-  // OutputSurface implementation
-  void SwapBuffers(CompositorFrame* frame) override;
+  explicit TestOutputSurface(
+      std::unique_ptr<ContextProvider::Factory> compositor_context_factory)
+      : OutputSurface(std::move(compositor_context_factory)) {}
+  ~TestOutputSurface() override = default;
+
+  // OutputSurface implementation.
+  void SwapBuffers(CompositorFrame* frame) override {
+    client_->DidSwapBuffers();
+    client_->DidSwapBuffersComplete();
+  }
 };
 
-TestOutputSurface::TestOutputSurface(
-    scoped_refptr<ContextProvider> context_provider)
-    : OutputSurface(std::move(context_provider)) {}
+class MockContextProvider : public TestContextProvider {
+ public:
+  MockContextProvider()
+      : TestContextProvider(TestWebGraphicsContext3D::Create()) {}
 
-TestOutputSurface::~TestOutputSurface() {
-}
+  class Factory : public ContextProvider::Factory {
+   public:
+    explicit Factory(scoped_refptr<MockContextProvider> provider)
+        : provider_(provider) {}
 
-void TestOutputSurface::SwapBuffers(CompositorFrame* frame) {
-  client_->DidSwapBuffers();
-  client_->DidSwapBuffersComplete();
-}
+    scoped_refptr<ContextProvider> CreateContext() override {
+      return std::move(provider_);
+    }
+
+   private:
+    scoped_refptr<MockContextProvider> provider_;
+  };
 
-class MockContextProvider : public TestContextProvider {
- public:
-  explicit MockContextProvider(
-      std::unique_ptr<TestWebGraphicsContext3D> context)
-      : TestContextProvider(std::move(context)) {}
   MOCK_METHOD0(DeleteCachedResources, void());
 
  protected:
-  ~MockContextProvider() {}
+  ~MockContextProvider() = default;
 };
 
 template <class T>
@@ -78,9 +84,9 @@ template <typename T>
 class RendererTest : public ::testing::Test {
  protected:
   virtual void SetUp() {
-    context_provider_ =
-        new MockContextProvider(TestWebGraphicsContext3D::Create());
-    output_surface_.reset(new TestOutputSurface(context_provider_));
+    context_provider_ = new MockContextProvider;
+    output_surface_.reset(new TestOutputSurface(
+        base::MakeUnique<MockContextProvider::Factory>(context_provider_)));
     output_surface_->BindToClient(&output_surface_client_);
     resource_provider_ =
         FakeResourceProvider::Create(output_surface_.get(), nullptr);
@@ -103,8 +109,7 @@ typedef ::testing::Types<DelegatingRenderer, GLRenderer> RendererTypes;
 TYPED_TEST_CASE(RendererTest, RendererTypes);
 
 TYPED_TEST(RendererTest, ContextPurgedWhenRendererBecomesInvisible) {
-  EXPECT_CALL(*(this->context_provider_.get()), DeleteCachedResources())
-      .Times(1);
+  EXPECT_CALL(*this->context_provider_, DeleteCachedResources()).Times(1);
 
   EXPECT_TRUE(this->renderer_->visible());
   this->renderer_->SetVisible(false);