cc: Make OutputSurface::SwapBuffers pure virtual

cc/test/fake_output_surface.h

 // Copyright 2012 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.
 
 #ifndef CC_TEST_FAKE_OUTPUT_SURFACE_H_
 #define CC_TEST_FAKE_OUTPUT_SURFACE_H_
 
 #include "base/callback.h"
 #include "base/logging.h"
 #include "base/time/time.h"
@@ skipping 101 matching lines @@
 
   virtual bool HasExternalStencilTest() const override;
 
   void set_has_external_stencil_test(bool has_test) {
     has_external_stencil_test_ = has_test;
   }
 
   void SetMemoryPolicyToSetAtBind(
       scoped_ptr<ManagedMemoryPolicy> memory_policy_to_set_at_bind);
 
+  gfx::Rect last_swap_rect() const {
+    return last_swap_rect_;
+  }
+
  protected:
   FakeOutputSurface(
       scoped_refptr<ContextProvider> context_provider,
       bool delegated_rendering);
 
   FakeOutputSurface(
       scoped_ptr<SoftwareOutputDevice> software_device,
       bool delegated_rendering);
 
   FakeOutputSurface(
       scoped_refptr<ContextProvider> context_provider,
       scoped_ptr<SoftwareOutputDevice> software_device,
       bool delegated_rendering);
 
   void OnBeginFrame();
 
   OutputSurfaceClient* client_;
   CompositorFrame last_sent_frame_;
   size_t num_sent_frames_;
   bool needs_begin_frame_;
   bool has_external_stencil_test_;
   TransferableResourceArray resources_held_by_parent_;
   scoped_ptr<ManagedMemoryPolicy> memory_policy_to_set_at_bind_;
+  gfx::Rect last_swap_rect_;
 
   base::WeakPtrFactory<FakeOutputSurface> fake_weak_ptr_factory_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_FAKE_OUTPUT_SURFACE_H_