[#2] Pass gfx structs by const ref (gfx::Rect, gfx::RectF)

cc/output/software_renderer.h

Index: cc/output/software_renderer.h
diff --git a/cc/output/software_renderer.h b/cc/output/software_renderer.h
index 18fb2a3fc335469ac3aa2d889c5f1f782a120e1b..1da90ee19ea33699ea2853da9afd1b075c7b34a7 100644
--- a/cc/output/software_renderer.h
+++ b/cc/output/software_renderer.h
@@ -37,7 +37,8 @@ class CC_EXPORT SoftwareRenderer : public DirectRenderer {
   virtual const RendererCapabilities& Capabilities() const OVERRIDE;
   virtual void Finish() OVERRIDE;
   virtual void SwapBuffers(const CompositorFrameMetadata& metadata) OVERRIDE;
-  virtual void GetFramebufferPixels(void* pixels, gfx::Rect rect) OVERRIDE;
+  virtual void GetFramebufferPixels(void* pixels,
+                                    const gfx::Rect& rect) OVERRIDE;
   virtual void SetVisible(bool visible) OVERRIDE;
   virtual void SendManagedMemoryStats(
       size_t bytes_visible,
@@ -53,9 +54,9 @@ class CC_EXPORT SoftwareRenderer : public DirectRenderer {
   virtual bool BindFramebufferToTexture(
       DrawingFrame* frame,
       const ScopedResource* texture,
-      gfx::Rect target_rect) OVERRIDE;
-  virtual void SetDrawViewport(gfx::Rect window_space_viewport) OVERRIDE;
-  virtual void SetScissorTestRect(gfx::Rect scissor_rect) OVERRIDE;
+      const gfx::Rect& target_rect) OVERRIDE;
+  virtual void SetDrawViewport(const gfx::Rect& window_space_viewport) OVERRIDE;
+  virtual void SetScissorTestRect(const gfx::Rect& scissor_rect) OVERRIDE;
   virtual void DiscardPixels(bool has_external_stencil_test,
                              bool draw_rect_covers_full_surface) OVERRIDE;
   virtual void ClearFramebuffer(DrawingFrame* frame,
@@ -77,7 +78,7 @@ class CC_EXPORT SoftwareRenderer : public DirectRenderer {
 
  private:
   void ClearCanvas(SkColor color);
-  void SetClipRect(gfx::Rect rect);
+  void SetClipRect(const gfx::Rect& rect);
   bool IsSoftwareResource(ResourceProvider::ResourceId resource_id) const;
 
   void DrawCheckerboardQuad(const DrawingFrame* frame,