cc: Make OutputSurface::BindToClient pure virtual and not return bool

cc/output/overlay_unittest.cc

Index: cc/output/overlay_unittest.cc
diff --git a/cc/output/overlay_unittest.cc b/cc/output/overlay_unittest.cc
index 01c14e041b5c1ed5e94e2115585d507ad63b6078..eb5fd8169a4873d6c044f99530e7dcf266ab8328 100644
--- a/cc/output/overlay_unittest.cc
+++ b/cc/output/overlay_unittest.cc
@@ -156,6 +156,7 @@ class OverlayOutputSurface : public OutputSurface {
   }
 
   // OutputSurface implementation.
+  void BindToClient(OutputSurfaceClient* client) override {}
   void EnsureBackbuffer() override {}
   void DiscardBackbuffer() override {}
   void BindFramebuffer() override {
@@ -181,8 +182,6 @@ class OverlayOutputSurface : public OutputSurface {
   unsigned GetOverlayTextureId() const override { return 10000; }
   bool SurfaceIsSuspendForRecycle() const override { return false; }
 
-  void OnSwapBuffersComplete() { client_->DidReceiveSwapBuffersAck(); }
-
   void set_is_displayed_as_overlay_plane(bool value) {
     is_displayed_as_overlay_plane_ = value;
   }
@@ -352,8 +351,9 @@ class OverlayTest : public testing::Test {
  protected:
   void SetUp() override {
     provider_ = TestContextProvider::Create();
+    provider_->BindToCurrentThread();
     output_surface_.reset(new OverlayOutputSurface(provider_));
-    EXPECT_TRUE(output_surface_->BindToClient(&client_));
+    output_surface_->BindToClient(&client_);
     output_surface_->SetOverlayCandidateValidator(
         new OverlayCandidateValidatorType);
 
@@ -390,9 +390,10 @@ TEST(OverlayTest, NoOverlaysByDefault) {
 
 TEST(OverlayTest, OverlaysProcessorHasStrategy) {
   scoped_refptr<TestContextProvider> provider = TestContextProvider::Create();
+  provider->BindToCurrentThread();
   OverlayOutputSurface output_surface(provider);
   FakeOutputSurfaceClient client;
-  EXPECT_TRUE(output_surface.BindToClient(&client));
+  output_surface.BindToClient(&client);
   output_surface.SetOverlayCandidateValidator(new SingleOverlayValidator);
 
   std::unique_ptr<SharedBitmapManager> shared_bitmap_manager(
@@ -1311,8 +1312,9 @@ class GLRendererWithOverlaysTest : public testing::Test {
  protected:
   GLRendererWithOverlaysTest() {
     provider_ = TestContextProvider::Create();
+    provider_->BindToCurrentThread();
     output_surface_.reset(new OverlayOutputSurface(provider_));
-    CHECK(output_surface_->BindToClient(&output_surface_client_));
+    output_surface_->BindToClient(&output_surface_client_);
     resource_provider_ = FakeResourceProvider::Create(provider_.get(), nullptr);
 
     provider_->support()->SetScheduleOverlayPlaneCallback(base::Bind(
@@ -1334,14 +1336,12 @@ class GLRendererWithOverlaysTest : public testing::Test {
   }
   void SwapBuffers() {
     renderer_->SwapBuffers(std::vector<ui::LatencyInfo>());
-    output_surface_->OnSwapBuffersComplete();
     renderer_->SwapBuffersComplete();
   }
   void SwapBuffersWithoutComplete() {
     renderer_->SwapBuffers(std::vector<ui::LatencyInfo>());
   }
   void SwapBuffersComplete() {
-    output_surface_->OnSwapBuffersComplete();
     renderer_->SwapBuffersComplete();
   }
   void ReturnResourceInUseQuery(ResourceId id) {