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

cc/trees/layer_tree_host_unittest.cc

 // Copyright 2011 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/trees/layer_tree_host.h"
 
 #include <algorithm>
 
 #include "base/auto_reset.h"
 #include "base/synchronization/lock.h"
@@ skipping 1576 matching lines @@
 };
 
 MULTI_THREAD_DELEGATING_RENDERER_NOIMPL_TEST_F(
     LayerTreeHostTestDelegatingRendererAtomicCommit);
 
 static void SetLayerPropertiesForTesting(Layer* layer,
                                          Layer* parent,
                                          const gfx::Transform& transform,
                                          const gfx::PointF& anchor,
                                          const gfx::PointF& position,
-                                         gfx::Size bounds,
+                                         const gfx::Size& bounds,
                                          bool opaque) {
   layer->RemoveAllChildren();
   if (parent)
     parent->AddChild(layer);
   layer->SetTransform(transform);
   layer->SetAnchorPoint(anchor);
   layer->SetPosition(position);
   layer->SetBounds(bounds);
   layer->SetContentsOpaque(opaque);
 }
@@ skipping 3341 matching lines @@
 
     EndTest();
   }
 
   virtual void AfterTest() OVERRIDE {}
 };
 
 MULTI_THREAD_TEST_F(LayerTreeHostTestSimpleSwapPromiseMonitor);
 
 }  // namespace cc