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

cc/layers/layer.cc

 // Copyright 2010 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/layers/layer.h"
 
 #include <algorithm>
 
 #include "base/debug/trace_event.h"
 #include "base/location.h"
@@ skipping 358 matching lines @@
 
 void Layer::RequestCopyOfOutput(
     scoped_ptr<CopyOutputRequest> request) {
   DCHECK(IsPropertyChangeAllowed());
   if (request->IsEmpty())
     return;
   copy_requests_.push_back(request.Pass());
   SetNeedsCommit();
 }
 
-void Layer::SetAnchorPoint(gfx::PointF anchor_point) {
+void Layer::SetAnchorPoint(const gfx::PointF& anchor_point) {
   DCHECK(IsPropertyChangeAllowed());
   if (anchor_point_ == anchor_point)
     return;
   anchor_point_ = anchor_point;
   SetNeedsCommit();
 }
 
 void Layer::SetAnchorPointZ(float anchor_point_z) {
   DCHECK(IsPropertyChangeAllowed());
   if (anchor_point_z_ == anchor_point_z)
@@ skipping 184 matching lines @@
 }
 
 void Layer::SetContentsOpaque(bool opaque) {
   DCHECK(IsPropertyChangeAllowed());
   if (contents_opaque_ == opaque)
     return;
   contents_opaque_ = opaque;
   SetNeedsCommit();
 }
 
-void Layer::SetPosition(gfx::PointF position) {
+void Layer::SetPosition(const gfx::PointF& position) {
   DCHECK(IsPropertyChangeAllowed());
   if (position_ == position)
     return;
   position_ = position;
   SetNeedsCommit();
 }
 
 bool Layer::IsContainerForFixedPositionLayers() const {
   if (!transform_.IsIdentityOrTranslation())
     return true;
@@ skipping 579 matching lines @@
     clip_parent_->RemoveClipChild(this);
 
   clip_parent_ = NULL;
 }
 
 void Layer::RunMicroBenchmark(MicroBenchmark* benchmark) {
   benchmark->RunOnLayer(this);
 }
 
 }  // namespace cc