[#2] Pass gfx structs by const ref (gfx::Rect, gfx::RectF)

cc/test/test_context_support.h

 // Copyright 2013 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_TEST_CONTEXT_SUPPORT_H_
 #define CC_TEST_TEST_CONTEXT_SUPPORT_H_
 
 #include <vector>
 
 #include "base/memory/weak_ptr.h"
 #include "gpu/command_buffer/client/context_support.h"
 
 namespace cc {
 
 class TestContextSupport : public gpu::ContextSupport {
  public:
   TestContextSupport();
   virtual ~TestContextSupport();
 
   // gpu::ContextSupport implementation.
   virtual void SignalSyncPoint(uint32 sync_point,
                                const base::Closure& callback) OVERRIDE;
   virtual void SignalQuery(uint32 query,
                            const base::Closure& callback) OVERRIDE;
   virtual void SetSurfaceVisible(bool visible) OVERRIDE;
   virtual void SendManagedMemoryStats(const gpu::ManagedMemoryStats& stats)
     OVERRIDE;
   virtual void Swap() OVERRIDE;
-  virtual void PartialSwapBuffers(gfx::Rect sub_buffer) OVERRIDE;
+  virtual void PartialSwapBuffers(const gfx::Rect& sub_buffer) OVERRIDE;
   virtual void SetSwapBuffersCompleteCallback(
       const base::Closure& callback) OVERRIDE;
 
   void CallAllSyncPointCallbacks();
 
   typedef base::Callback<void(bool visible)> SurfaceVisibleCallback;
   void SetSurfaceVisibleCallback(
       const SurfaceVisibleCallback& set_visible_callback);
 
   enum SwapType {
@@ skipping 19 matching lines @@
   gfx::Rect last_partial_swap_rect_;
 
   base::WeakPtrFactory<TestContextSupport> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(TestContextSupport);
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_TEST_CONTEXT_SUPPORT_H_