cc: Make OutputSurface::SwapBuffers pure virtual

cc/output/overlay_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/base/scoped_ptr_vector.h"
 #include "cc/output/gl_renderer.h"
 #include "cc/output/output_surface.h"
 #include "cc/output/output_surface_client.h"
 #include "cc/output/overlay_candidate_validator.h"
 #include "cc/output/overlay_processor.h"
@@ skipping 84 matching lines @@
 
 size_t DefaultOverlayProcessor::GetStrategyCount() {
   return strategies_.size();
 }
 
 class OverlayOutputSurface : public OutputSurface {
  public:
   explicit OverlayOutputSurface(scoped_refptr<ContextProvider> context_provider)
       : OutputSurface(context_provider) {}
 
+  // OutputSurface implementation
+  virtual void SwapBuffers(CompositorFrame* frame) override;
+
   void InitWithSingleOverlayValidator() {
     overlay_candidate_validator_.reset(new SingleOverlayValidator);
   }
 };
 
+void OverlayOutputSurface::SwapBuffers(CompositorFrame* frame) {
+  client_->DidSwapBuffers();
+  client_->DidSwapBuffersComplete();
+}
+
 scoped_ptr<RenderPass> CreateRenderPass() {
   RenderPassId id(1, 0);
   gfx::Rect output_rect(0, 0, 256, 256);
   bool has_transparent_background = true;
 
   scoped_ptr<RenderPass> pass = RenderPass::Create();
   pass->SetAll(id,
                output_rect,
                output_rect,
                gfx::Transform(),
@@ skipping 661 matching lines @@
   renderer_->set_expect_overlays(false);
   renderer_->FinishDrawingFrame(&frame3);
   EXPECT_TRUE(resource_provider_->InUseByConsumer(resource1));
   SwapBuffers();
   EXPECT_FALSE(resource_provider_->InUseByConsumer(resource1));
   Mock::VerifyAndClearExpectations(&scheduler_);
 }
 
 }  // namespace
 }  // namespace cc