Defer compositor context creation to the thread.

cc/output/gl_renderer_unittest.cc

Index: cc/output/gl_renderer_unittest.cc
diff --git a/cc/output/gl_renderer_unittest.cc b/cc/output/gl_renderer_unittest.cc
index 0048cda6a759c6f40d7ef11f621857c9a4415527..bfbe9119d9f68677a7d24e3496177c8adc294ef4 100644
--- a/cc/output/gl_renderer_unittest.cc
+++ b/cc/output/gl_renderer_unittest.cc
@@ -1139,7 +1139,8 @@ class NonReshapableOutputSurface : public FakeOutputSurface {
  public:
   explicit NonReshapableOutputSurface(
       std::unique_ptr<TestWebGraphicsContext3D> context3d)
-      : FakeOutputSurface(TestContextProvider::Create(std::move(context3d)),
+      : FakeOutputSurface(base::MakeUnique<TestContextProvider::Factory>(
+                              std::move(context3d)),
                           false) {
     surface_size_ = gfx::Size(500, 500);
   }
@@ -1762,9 +1763,8 @@ class OutputSurfaceMockContext : public TestWebGraphicsContext3D {
 class MockOutputSurface : public OutputSurface {
  public:
   MockOutputSurface()
-      : OutputSurface(TestContextProvider::Create(
-            std::unique_ptr<TestWebGraphicsContext3D>(
-                new StrictMock<OutputSurfaceMockContext>))) {
+      : OutputSurface(base::MakeUnique<TestContextProvider::Factory>(
+            base::MakeUnique<StrictMock<OutputSurfaceMockContext>>())) {
     surface_size_ = gfx::Size(100, 100);
   }
   virtual ~MockOutputSurface() {}
@@ -2083,15 +2083,16 @@ TEST_F(GLRendererTest, OverlaySyncTokensAreProcessed) {
   WaitSyncTokenCountingContext* context = context_owned.get();
 
   MockOverlayScheduler overlay_scheduler;
-  scoped_refptr<TestContextProvider> context_provider =
-      TestContextProvider::Create(std::move(context_owned));
-  context_provider->support()->SetScheduleOverlayPlaneCallback(base::Bind(
-      &MockOverlayScheduler::Schedule, base::Unretained(&overlay_scheduler)));
-
   FakeOutputSurfaceClient output_surface_client;
-  std::unique_ptr<OutputSurface> output_surface(
-      FakeOutputSurface::Create3d(context_provider));
+  std::unique_ptr<OutputSurface> output_surface(FakeOutputSurface::Create3d(
+      base::MakeUnique<TestContextProvider::Factory>(
+          std::move(context_owned))));
   CHECK(output_surface->BindToClient(&output_surface_client));
+  TestContextProvider* context_provider =
+      static_cast<TestContextProvider*>(output_surface->context_provider());
+
+  context_provider->support()->SetScheduleOverlayPlaneCallback(base::Bind(
+      &MockOverlayScheduler::Schedule, base::Unretained(&overlay_scheduler)));
 
   std::unique_ptr<SharedBitmapManager> shared_bitmap_manager(
       new TestSharedBitmapManager());