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

cc/layers/layer.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_LAYER_H_
 #define CC_LAYERS_LAYER_H_
 
 #include <set>
 #include <string>
 
@@ skipping 84 matching lines @@
   Layer* child_at(size_t index) { return children_[index].get(); }
 
   // This requests the layer and its subtree be rendered and given to the
   // callback. If the copy is unable to be produced (the layer is destroyed
   // first), then the callback is called with a NULL/empty result.
   void RequestCopyOfOutput(scoped_ptr<CopyOutputRequest> request);
   bool HasCopyRequest() const {
     return !copy_requests_.empty();
   }
 
-  void SetAnchorPoint(gfx::PointF anchor_point);
+  void SetAnchorPoint(const gfx::PointF& anchor_point);
   gfx::PointF anchor_point() const { return anchor_point_; }
 
   void SetAnchorPointZ(float anchor_point_z);
   float anchor_point_z() const { return anchor_point_z_; }
 
   virtual void SetBackgroundColor(SkColor background_color);
   SkColor background_color() const { return background_color_; }
   // If contents_opaque(), return an opaque color else return a
   // non-opaque color.  Tries to return background_color(), if possible.
   SkColor SafeOpaqueBackgroundColor() const;
@@ skipping 42 matching lines @@
   // they are viewed through non-opaque regions in this layer. They are used
   // through the WebLayer interface, and are not exposed to HTML.
   void SetBackgroundFilters(const FilterOperations& filters);
   const FilterOperations& background_filters() const {
     return background_filters_;
   }
 
   virtual void SetContentsOpaque(bool opaque);
   bool contents_opaque() const { return contents_opaque_; }
 
-  void SetPosition(gfx::PointF position);
+  void SetPosition(const gfx::PointF& position);
   gfx::PointF position() const { return position_; }
 
   void SetIsContainerForFixedPositionLayers(bool container);
   bool IsContainerForFixedPositionLayers() const;
 
   void SetPositionConstraint(const LayerPositionConstraint& constraint);
   const LayerPositionConstraint& position_constraint() const {
     return position_constraint_;
   }
 
@@ skipping 442 matching lines @@
   DrawProperties<Layer> draw_properties_;
 
   PaintProperties paint_properties_;
 
   DISALLOW_COPY_AND_ASSIGN(Layer);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_LAYER_H_