sync compositor: pass simple gfx types by const ref

content/browser/android/in_process/synchronous_compositor_impl.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 CONTENT_BROWSER_ANDROID_IN_PROCESS_SYNCHRONOUS_COMPOSITOR_IMPL_H_
 #define CONTENT_BROWSER_ANDROID_IN_PROCESS_SYNCHRONOUS_COMPOSITOR_IMPL_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 54 matching lines @@
   void OnNeedsBeginFramesChange(bool needs_begin_frames) override;
 
   // SynchronousCompositorOutputSurfaceClient overrides.
   void Invalidate() override;
 
   // Called by RenderWidgetHostViewAndroid.
   void BeginFrame(const cc::BeginFrameArgs& args);
 
   // SynchronousCompositor
   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;
   bool DemandDrawSw(SkCanvas* canvas) override;
   void ReturnResources(const cc::CompositorFrameAck& frame_ack) 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 animation_time) override;
 
   // SynchronousInputHandler
@@ skipping 30 matching lines @@
   bool need_animate_input_;
 
   base::WeakPtrFactory<SynchronousCompositorImpl> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SynchronousCompositorImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_IN_PROCESS_SYNCHRONOUS_COMPOSITOR_IMPL_H_