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

cc/output/software_renderer.cc

 // 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.
 
 #include "cc/output/software_renderer.h"
 
 #include "base/debug/trace_event.h"
 #include "cc/base/math_util.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/output/compositor_frame_ack.h"
@@ skipping 139 matching lines @@
 
 void SoftwareRenderer::BindFramebufferToOutputSurface(DrawingFrame* frame) {
   DCHECK(!output_surface_->HasExternalStencilTest());
   current_framebuffer_lock_.reset();
   current_canvas_ = root_canvas_;
 }
 
 bool SoftwareRenderer::BindFramebufferToTexture(
     DrawingFrame* frame,
     const ScopedResource* texture,
-    gfx::Rect target_rect) {
+    const gfx::Rect& target_rect) {
   current_framebuffer_lock_.reset();
   current_framebuffer_lock_ = make_scoped_ptr(
       new ResourceProvider::ScopedWriteLockSoftware(
           resource_provider_, texture->id()));
   current_canvas_ = current_framebuffer_lock_->sk_canvas();
   InitializeViewport(frame,
                      target_rect,
                      gfx::Rect(target_rect.size()),
                      target_rect.size());
   return true;
 }
 
-void SoftwareRenderer::SetScissorTestRect(gfx::Rect scissor_rect) {
+void SoftwareRenderer::SetScissorTestRect(const gfx::Rect& scissor_rect) {
   is_scissor_enabled_ = true;
   scissor_rect_ = scissor_rect;
   SetClipRect(scissor_rect);
 }
 
-void SoftwareRenderer::SetClipRect(gfx::Rect rect) {
+void SoftwareRenderer::SetClipRect(const gfx::Rect& rect) {
   // Skia applies the current matrix to clip rects so we reset it temporary.
   SkMatrix current_matrix = current_canvas_->getTotalMatrix();
   current_canvas_->resetMatrix();
   current_canvas_->clipRect(gfx::RectToSkRect(rect), SkRegion::kReplace_Op);
   current_canvas_->setMatrix(current_matrix);
 }
 
 void SoftwareRenderer::ClearCanvas(SkColor color) {
   // SkCanvas::clear doesn't respect the current clipping region
   // so we SkCanvas::drawColor instead if scissoring is active.
@@ skipping 12 matching lines @@
     ClearCanvas(SkColorSetARGB(0, 0, 0, 0));
   } else {
 #ifndef NDEBUG
     // On DEBUG builds, opaque render passes are cleared to blue
     // to easily see regions that were not drawn on the screen.
     ClearCanvas(SkColorSetARGB(255, 0, 0, 255));
 #endif
   }
 }
 
-void SoftwareRenderer::SetDrawViewport(gfx::Rect window_space_viewport) {}
+void SoftwareRenderer::SetDrawViewport(
+    const gfx::Rect& window_space_viewport) {}
 
 bool SoftwareRenderer::IsSoftwareResource(
     ResourceProvider::ResourceId resource_id) const {
   switch (resource_provider_->GetResourceType(resource_id)) {
     case ResourceProvider::GLTexture:
       return false;
     case ResourceProvider::Bitmap:
       return true;
     case ResourceProvider::InvalidType:
       break;
@@ skipping 357 matching lines @@
 }
 
 void SoftwareRenderer::EnsureBackbuffer() {
   if (!is_backbuffer_discarded_)
     return;
 
   output_surface_->EnsureBackbuffer();
   is_backbuffer_discarded_ = false;
 }
 
-void SoftwareRenderer::GetFramebufferPixels(void* pixels, gfx::Rect rect) {
+void SoftwareRenderer::GetFramebufferPixels(void* pixels,
+                                            const gfx::Rect& rect) {
   TRACE_EVENT0("cc", "SoftwareRenderer::GetFramebufferPixels");
   SkBitmap subset_bitmap;
-  rect += current_viewport_rect_.OffsetFromOrigin();
-  output_device_->CopyToBitmap(rect, &subset_bitmap);
+  gfx::Rect frame_rect(rect);
+  frame_rect += current_viewport_rect_.OffsetFromOrigin();
+  output_device_->CopyToBitmap(frame_rect, &subset_bitmap);
   subset_bitmap.copyPixelsTo(pixels,
-                             4 * rect.width() * rect.height(),
-                             4 * rect.width());
+                             4 * frame_rect.width() * frame_rect.height(),
+                             4 * frame_rect.width());
 }
 
 void SoftwareRenderer::SetVisible(bool visible) {
   if (visible_ == visible)
     return;
   visible_ = visible;
 
   if (visible_)
     EnsureBackbuffer();
   else
     DiscardBackbuffer();
 }
 
 }  // namespace cc