[#3] Pass gfx structs by const ref (gfx::SizeF)

cc/base/math_util.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/base/math_util.h"
 
 #include <algorithm>
 #include <cmath>
 #include <limits>
 
@@ skipping 496 matching lines @@
                         projected_length * destination.y());
 }
 
 scoped_ptr<base::Value> MathUtil::AsValue(gfx::Size s) {
   scoped_ptr<base::DictionaryValue> res(new base::DictionaryValue());
   res->SetDouble("width", s.width());
   res->SetDouble("height", s.height());
   return res.PassAs<base::Value>();
 }
 
-scoped_ptr<base::Value> MathUtil::AsValue(gfx::SizeF s) {
+scoped_ptr<base::Value> MathUtil::AsValue(const gfx::SizeF& s) {
   scoped_ptr<base::DictionaryValue> res(new base::DictionaryValue());
   res->SetDouble("width", s.width());
   res->SetDouble("height", s.height());
   return res.PassAs<base::Value>();
 }
 
 scoped_ptr<base::Value> MathUtil::AsValue(const gfx::Rect& r) {
   scoped_ptr<base::ListValue> res(new base::ListValue());
   res->AppendInteger(r.x());
   res->AppendInteger(r.y());
@@ skipping 77 matching lines @@
   return scoped_ptr<base::Value>(base::Value::CreateDoubleValue(
       std::min(value, std::numeric_limits<double>::max())));
 }
 
 scoped_ptr<base::Value> MathUtil::AsValueSafely(float value) {
   return scoped_ptr<base::Value>(base::Value::CreateDoubleValue(
       std::min(value, std::numeric_limits<float>::max())));
 }
 
 }  // namespace cc