[#4] Pass gfx structs by const ref (gfx::PointF)

cc/layers/ui_resource_layer_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 CC_LAYERS_UI_RESOURCE_LAYER_IMPL_H_
 #define CC_LAYERS_UI_RESOURCE_LAYER_IMPL_H_
 
 #include <string>
 
 #include "cc/base/cc_export.h"
@@ skipping 15 matching lines @@
                                                int id) {
     return make_scoped_ptr(new UIResourceLayerImpl(tree_impl, id));
   }
   virtual ~UIResourceLayerImpl();
 
   void SetUIResourceId(UIResourceId uid);
 
   void SetImageBounds(gfx::Size image_bounds);
 
   // Sets a UV transform to be used at draw time. Defaults to (0, 0) and (1, 1).
-  void SetUV(gfx::PointF top_left, gfx::PointF bottom_right);
+  void SetUV(const gfx::PointF& top_left, const gfx::PointF& bottom_right);
 
   // Sets an opacity value per vertex. It will be multiplied by the layer
   // opacity value.
   void SetVertexOpacity(const float vertex_opacity[4]);
 
   virtual scoped_ptr<LayerImpl> CreateLayerImpl(LayerTreeImpl* tree_impl)
       OVERRIDE;
   virtual void PushPropertiesTo(LayerImpl* layer) OVERRIDE;
 
   virtual bool WillDraw(DrawMode draw_mode,
@@ skipping 17 matching lines @@
 
  private:
   virtual const char* LayerTypeAsString() const OVERRIDE;
 
   DISALLOW_COPY_AND_ASSIGN(UIResourceLayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_UI_RESOURCE_LAYER_IMPL_H_