Defer compositor context creation to the thread.

cc/trees/layer_tree_host_unittest.cc

Index: cc/trees/layer_tree_host_unittest.cc
diff --git a/cc/trees/layer_tree_host_unittest.cc b/cc/trees/layer_tree_host_unittest.cc
index dd9af8d18f5440d958a335d21f2d10ac681f066f..a43f2b28390bb532fe91129274d2dd1f3027d6d2 100644
--- a/cc/trees/layer_tree_host_unittest.cc
+++ b/cc/trees/layer_tree_host_unittest.cc
@@ -471,8 +471,8 @@ class LayerTreeHostFreeWorkerContextResourcesTest : public LayerTreeHostTest {
     ~MockSetWorkerContextShouldAggressivelyFreeResourcesOutputSurface() {}
     explicit MockSetWorkerContextShouldAggressivelyFreeResourcesOutputSurface(
         bool delegated_rendering)
-        : FakeOutputSurface(TestContextProvider::Create(),
-                            TestContextProvider::CreateWorker(),
+        : FakeOutputSurface(base::MakeUnique<TestContextProvider::Factory>(),
+                            TestContextProvider::Create(),
                             delegated_rendering) {}
     MOCK_METHOD1(SetWorkerContextShouldAggressivelyFreeResources,
                  void(bool is_visible));
@@ -4144,35 +4144,33 @@ MULTI_THREAD_TEST_F(LayerTreeHostTestElasticOverscroll);
 class LayerTreeHostTestSetMemoryPolicyOnLostOutputSurface
     : public LayerTreeHostTest {
  protected:
-  LayerTreeHostTestSetMemoryPolicyOnLostOutputSurface()
-      : first_output_surface_memory_limit_(4321234),
-        second_output_surface_memory_limit_(1234321) {}
-
   std::unique_ptr<FakeOutputSurface> CreateFakeOutputSurface() override {
-    if (!first_context_provider_.get()) {
-      first_context_provider_ = TestContextProvider::Create();
-    } else {
-      EXPECT_FALSE(second_context_provider_.get());
-      second_context_provider_ = TestContextProvider::Create();
-    }
-
-    scoped_refptr<TestContextProvider> provider(second_context_provider_.get()
-                                                    ? second_context_provider_
-                                                    : first_context_provider_);
+    std::unique_ptr<TestContextProvider::Factory> create(
+        new TestContextProvider::Factory);
+    const bool first = !first_context_provider_;
     std::unique_ptr<FakeOutputSurface> output_surface;
     if (delegating_renderer())
-      output_surface = FakeOutputSurface::CreateDelegating3d(provider);
+      output_surface = FakeOutputSurface::CreateDelegating3d(std::move(create));
     else
-      output_surface = FakeOutputSurface::Create3d(provider);
+      output_surface = FakeOutputSurface::Create3d(std::move(create));
     output_surface->SetMemoryPolicyToSetAtBind(
         base::WrapUnique(new ManagedMemoryPolicy(
-            second_context_provider_.get() ? second_output_surface_memory_limit_
-                                           : first_output_surface_memory_limit_,
+            first ? first_output_surface_memory_limit_
+                  : second_output_surface_memory_limit_,
             gpu::MemoryAllocation::CUTOFF_ALLOW_NICE_TO_HAVE,
             ManagedMemoryPolicy::kDefaultNumResourcesLimit)));
     return output_surface;
   }
 
+  void InitializedRendererOnThread(LayerTreeHostImpl* impl,
+                                   bool success) override {
+    ASSERT_TRUE(success);
+    if (!first_context_provider_) {
+      first_context_provider_ = static_cast<TestContextProvider*>(
+          impl->output_surface()->context_provider());
+    }
+  }
+
   void SetupTree() override {
     root_ = FakePictureLayer::Create(&client_);
     root_->SetBounds(gfx::Size(20, 20));
@@ -4212,10 +4210,9 @@ class LayerTreeHostTestSetMemoryPolicyOnLostOutputSurface
 
   void AfterTest() override {}
 
-  scoped_refptr<TestContextProvider> first_context_provider_;
-  scoped_refptr<TestContextProvider> second_context_provider_;
-  size_t first_output_surface_memory_limit_;
-  size_t second_output_surface_memory_limit_;
+  TestContextProvider* first_context_provider_ = nullptr;
+  size_t first_output_surface_memory_limit_ = 4321234;
+  size_t second_output_surface_memory_limit_ = 1234321;
   FakeContentLayerClient client_;
   scoped_refptr<Layer> root_;
 };
@@ -5472,7 +5469,6 @@ class LayerTreeHostTestCrispUpAfterPinchEndsWithOneCopy
   std::unique_ptr<FakeOutputSurface> CreateFakeOutputSurface() override {
     std::unique_ptr<TestWebGraphicsContext3D> context3d =
         TestWebGraphicsContext3D::Create();
-    context3d->set_support_image(true);
     context3d->set_support_sync_query(true);
 #if defined(OS_MACOSX)
     context3d->set_support_texture_rectangle(true);