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

cc/base/tiling_data.h

Index: cc/base/tiling_data.h
diff --git a/cc/base/tiling_data.h b/cc/base/tiling_data.h
index 9540c3896b1e3999522f5e34a626ad95cb327b27..96e6ae080384bb1472f2ecc56d09ef6348b76f07 100644
--- a/cc/base/tiling_data.h
+++ b/cc/base/tiling_data.h
@@ -23,19 +23,19 @@
  public:
   TilingData();
   TilingData(
-      const gfx::Size& max_texture_size,
-      const gfx::Size& total_size,
+      gfx::Size max_texture_size,
+      gfx::Size total_size,
       bool has_border_texels);
   TilingData(
-      const gfx::Size& max_texture_size,
-      const gfx::Size& total_size,
+      gfx::Size max_texture_size,
+      gfx::Size total_size,
       int border_texels);
 
   gfx::Size total_size() const { return total_size_; }
-  void SetTotalSize(const gfx::Size& total_size);
+  void SetTotalSize(const gfx::Size total_size);
 
   gfx::Size max_texture_size() const { return max_texture_size_; }
-  void SetMaxTextureSize(const gfx::Size& max_texture_size);
+  void SetMaxTextureSize(gfx::Size max_texture_size);
 
   int border_texels() const { return border_texels_; }
   void SetHasBorderTexels(bool has_border_texels);