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

cc/layers/tiled_layer_impl.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/layers/tiled_layer_impl.h"
 
 #include "base/basictypes.h"
 #include "base/strings/stringprintf.h"
 #include "cc/base/math_util.h"
 #include "cc/debug/debug_colors.h"
@@ skipping 245 matching lines @@
                                          ? LayerTilingData::HAS_BORDER_TEXELS
                                          : LayerTilingData::NO_BORDER_TEXELS);
   }
   *tiler_ = tiler;
 }
 
 void TiledLayerImpl::PushTileProperties(
     int i,
     int j,
     ResourceProvider::ResourceId resource_id,
-    gfx::Rect opaque_rect,
+    const gfx::Rect& opaque_rect,
     bool contents_swizzled) {
   DrawableTile* tile = TileAt(i, j);
   if (!tile)
     tile = CreateTile(i, j);
   tile->set_resource_id(resource_id);
   tile->set_opaque_rect(opaque_rect);
   tile->set_contents_swizzled(contents_swizzled);
 }
 
 void TiledLayerImpl::PushInvalidTile(int i, int j) {
@@ skipping 15 matching lines @@
 
 void TiledLayerImpl::DidLoseOutputSurface() {
   tiler_->reset();
 }
 
 const char* TiledLayerImpl::LayerTypeAsString() const {
   return "cc::TiledLayerImpl";
 }
 
 }  // namespace cc