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

cc/layers/texture_layer_impl.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_LAYERS_TEXTURE_LAYER_IMPL_H_
 #define CC_LAYERS_TEXTURE_LAYER_IMPL_H_
 
 #include <string>
 
 #include "base/callback.h"
@@ skipping 27 matching lines @@
 
   unsigned texture_id() const { return texture_id_; }
   void set_texture_id(unsigned id) { texture_id_ = id; }
   void set_premultiplied_alpha(bool premultiplied_alpha) {
     premultiplied_alpha_ = premultiplied_alpha;
   }
   void set_blend_background_color(bool blend) {
     blend_background_color_ = blend;
   }
   void set_flipped(bool flipped) { flipped_ = flipped; }
-  void set_uv_top_left(gfx::PointF top_left) { uv_top_left_ = top_left; }
-  void set_uv_bottom_right(gfx::PointF bottom_right) {
+  void set_uv_top_left(const gfx::PointF& top_left) { uv_top_left_ = top_left; }
+  void set_uv_bottom_right(const gfx::PointF& bottom_right) {
     uv_bottom_right_ = bottom_right;
   }
 
   // 1--2
   // |  |
   // 0--3
   void set_vertex_opacity(const float vertex_opacity[4]) {
     vertex_opacity_[0] = vertex_opacity[0];
     vertex_opacity_[1] = vertex_opacity[1];
     vertex_opacity_[2] = vertex_opacity[2];
@@ skipping 25 matching lines @@
   bool uses_mailbox_;
   bool own_mailbox_;
   bool valid_texture_copy_;
 
   DISALLOW_COPY_AND_ASSIGN(TextureLayerImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_LAYERS_TEXTURE_LAYER_IMPL_H_