sync compositor: pass simple gfx types by const ref

content/public/test/test_synchronous_compositor_android.h

 // 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.
 
 #ifndef CONTENT_PUBLIC_TEST_TEST_SYNCHRONOUS_COMPOSITOR_ANDROID_H_
 #define CONTENT_PUBLIC_TEST_TEST_SYNCHRONOUS_COMPOSITOR_ANDROID_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "content/public/browser/android/synchronous_compositor.h"
 #include "content/public/browser/android/synchronous_compositor_client.h"
 
 namespace content {
 
 class CONTENT_EXPORT TestSynchronousCompositor : public SynchronousCompositor {
  public:
   TestSynchronousCompositor();
   ~TestSynchronousCompositor() override;
 
   void SetClient(SynchronousCompositorClient* client);
 
   // SynchronousCompositor overrides.
   scoped_ptr<cc::CompositorFrame> DemandDrawHw(
-      gfx::Size surface_size,
+      const gfx::Size& surface_size,
       const gfx::Transform& transform,
-      gfx::Rect viewport,
-      gfx::Rect clip,
-      gfx::Rect viewport_rect_for_tile_priority,
+      const gfx::Rect& viewport,
+      const gfx::Rect& clip,
+      const gfx::Rect& viewport_rect_for_tile_priority,
       const gfx::Transform& transform_for_tile_priority) override;
   void ReturnResources(const cc::CompositorFrameAck& frame_ack) override {}
   bool DemandDrawSw(SkCanvas* canvas) override;
   void SetMemoryPolicy(size_t bytes_limit) override {}
   void DidChangeRootLayerScrollOffset(
       const gfx::ScrollOffset& root_offset) override {}
   void SetIsActive(bool is_active) override {}
   void OnComputeScroll(base::TimeTicks animate_time) override {}
 
   void SetHardwareFrame(scoped_ptr<cc::CompositorFrame> frame);
 
  private:
   SynchronousCompositorClient* client_;
   scoped_ptr<cc::CompositorFrame> hardware_frame_;
 
   DISALLOW_COPY_AND_ASSIGN(TestSynchronousCompositor);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_TEST_TEST_SYNCHRONOUS_COMPOSITOR_ANDROID_H_