Revert of "Converted LayerImpl::bounds() to return SizeF."

cc/trees/layer_tree_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/trees/layer_tree_impl.h"
 
 #include <limits>
 #include <set>
 
 #include "base/debug/trace_event.h"
@@ skipping 552 matching lines @@
       "CalcDrawProperties should not set_needs_update_draw_properties()";
   return true;
 }
 
 const LayerImplList& LayerTreeImpl::RenderSurfaceLayerList() const {
   // If this assert triggers, then the list is dirty.
   DCHECK(!needs_update_draw_properties_);
   return render_surface_layer_list_;
 }
 
-gfx::SizeF LayerTreeImpl::ScrollableSize() const {
+gfx::Size LayerTreeImpl::ScrollableSize() const {
   LayerImpl* root_scroll_layer = OuterViewportScrollLayer()
                                      ? OuterViewportScrollLayer()
                                      : InnerViewportScrollLayer();
   if (!root_scroll_layer || root_scroll_layer->children().empty())
-    return gfx::SizeF();
+    return gfx::Size();
   return root_scroll_layer->children()[0]->bounds();
 }
 
 LayerImpl* LayerTreeImpl::LayerById(int id) {
   LayerIdMap::iterator iter = layer_id_map_.find(id);
   return iter != layer_id_map_.end() ? iter->second : NULL;
 }
 
 void LayerTreeImpl::RegisterLayer(LayerImpl* layer) {
   DCHECK(!LayerById(layer->id()));
@@ skipping 916 matching lines @@
                                   page_scale,
                                   duration.InSecondsF());
   }
 }
 
 scoped_ptr<PageScaleAnimation> LayerTreeImpl::TakePageScaleAnimation() {
   return page_scale_animation_.Pass();
 }
 
 }  // namespace cc