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

cc/quads/draw_quad.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_QUADS_DRAW_QUAD_H_
 #define CC_QUADS_DRAW_QUAD_H_
 
 #include "base/callback.h"
 #include "cc/base/cc_export.h"
 #include "cc/quads/shared_quad_state.h"
@@ skipping 113 matching lines @@
     return IsLeftEdge() || IsTopEdge() || IsRightEdge() || IsBottomEdge();
   }
 
   scoped_ptr<base::Value> AsValue() const;
 
  protected:
   DrawQuad();
 
   void SetAll(const SharedQuadState* shared_quad_state,
               Material material,
-              gfx::Rect rect,
-              gfx::Rect opaque_rect,
-              gfx::Rect visible_rect,
+              const gfx::Rect& rect,
+              const gfx::Rect& opaque_rect,
+              const gfx::Rect& visible_rect,
               bool needs_blending);
   virtual void ExtendValue(base::DictionaryValue* value) const = 0;
 };
 
 }  // namespace cc
 
 #endif  // CC_QUADS_DRAW_QUAD_H_