[#7] Pass gfx structs by const ref (gfx::Size)

cc/output/shader.h

 // Copyright 2011 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_OUTPUT_SHADER_H_
 #define CC_OUTPUT_SHADER_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 35 matching lines @@
 CC_EXPORT TexCoordPrecision TexCoordPrecisionRequired(
     gpu::gles2::GLES2Interface* context,
     int *highp_threshold_cache,
     int highp_threshold_min,
     gfx::Point max_coordinate);
 
 CC_EXPORT TexCoordPrecision TexCoordPrecisionRequired(
     gpu::gles2::GLES2Interface* context,
     int *highp_threshold_cache,
     int highp_threshold_min,
-    gfx::Size max_size);
+    const gfx::Size& max_size);
 
 class VertexShaderPosTex {
  public:
   VertexShaderPosTex();
 
   void Init(gpu::gles2::GLES2Interface* context,
             unsigned program,
             int* base_uniform_index);
   std::string GetShaderString() const;
 
@@ skipping 657 matching lines @@
   int tex_transform_location_;
   int frequency_location_;
   int color_location_;
 
   DISALLOW_COPY_AND_ASSIGN(FragmentShaderCheckerboard);
 };
 
 }  // namespace cc
 
 #endif  // CC_OUTPUT_SHADER_H_