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

cc/layers/render_surface.h

 // Copyright 2010 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_LAYERS_RENDER_SURFACE_H_
 #define CC_LAYERS_RENDER_SURFACE_H_
 
 #include <vector>
 
@@ skipping 11 matching lines @@
 
 class CC_EXPORT RenderSurface {
  public:
   explicit RenderSurface(Layer* owning_layer);
   ~RenderSurface();
 
   // Returns the rect that encloses the RenderSurfaceImpl including any
   // reflection.
   gfx::RectF DrawableContentRect() const;
 
-  void SetContentRect(gfx::Rect content_rect) { content_rect_ = content_rect; }
+  void SetContentRect(const gfx::Rect& content_rect) {
+      content_rect_ = content_rect;
+  }
   gfx::Rect content_rect() const { return content_rect_; }
 
   void SetDrawOpacity(float opacity) { draw_opacity_ = opacity; }
   float draw_opacity() const { return draw_opacity_; }
 
   void SetDrawOpacityIsAnimating(bool draw_opacity_is_animating) {
     draw_opacity_is_animating_ = draw_opacity_is_animating;
   }
   bool draw_opacity_is_animating() const { return draw_opacity_is_animating_; }
 
@@ skipping 34 matching lines @@
     screen_space_transforms_are_animating_ = animating;
   }
   bool screen_space_transforms_are_animating() const {
     return screen_space_transforms_are_animating_;
   }
 
   bool is_clipped() const { return is_clipped_; }
   void SetIsClipped(bool is_clipped) { is_clipped_ = is_clipped; }
 
   gfx::Rect clip_rect() const { return clip_rect_; }
-  void SetClipRect(gfx::Rect clip_rect) { clip_rect_ = clip_rect; }
+  void SetClipRect(const gfx::Rect& clip_rect) { clip_rect_ = clip_rect; }
 
   // When false, the RenderSurface does not contribute to another target
   // RenderSurface that is being drawn for the current frame. It could still be
   // drawn to as a target, but its output will not be a part of any other
   // surface.
   bool contributes_to_drawn_surface() const {
     return contributes_to_drawn_surface_;
   }
   void set_contributes_to_drawn_surface(bool contributes_to_drawn_surface) {
     contributes_to_drawn_surface_ = contributes_to_drawn_surface;
@@ skipping 42 matching lines @@
 
   // For LayerIteratorActions
   int target_render_surface_layer_index_history_;
   int current_layer_index_history_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderSurface);
 };
 
 }  // namespace cc
 #endif  // CC_LAYERS_RENDER_SURFACE_H_