Refactor cc scrollbar layers to separate solid-color vs desktop.

cc/layers/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/layer_impl.h"
 
 #include "base/debug/trace_event.h"
 #include "base/strings/stringprintf.h"
 #include "cc/animation/animation_registrar.h"
 #include "cc/animation/scrollbar_animation_controller.h"
@@ skipping 576 matching lines @@
   if (replica_layer_)
     replica_layer_->set_parent(this);
   NoteLayerPropertyChangedForSubtree();
 }
 
 scoped_ptr<LayerImpl> LayerImpl::TakeReplicaLayer() {
   replica_layer_id_ = -1;
   return replica_layer_.Pass();
 }
 
-ScrollbarLayerImpl* LayerImpl::ToScrollbarLayer() {
+ScrollbarLayerImplBase* LayerImpl::ToScrollbarLayerBase() {
   return NULL;
 }
 
 void LayerImpl::SetDrawsContent(bool draws_content) {
   if (draws_content_ == draws_content)
     return;
 
   draws_content_ = draws_content;
   NoteLayerPropertyChanged();
 }
@@ skipping 337 matching lines @@
       scrollbar_animation_controller_ =
           ScrollbarAnimationControllerLinearFade::Create(
               this, fadeout_delay, fadeout_length)
               .PassAs<ScrollbarAnimationController>();
     }
   } else {
     scrollbar_animation_controller_.reset();
   }
 }
 void LayerImpl::SetHorizontalScrollbarLayer(
-    ScrollbarLayerImpl* scrollbar_layer) {
+    ScrollbarLayerImplBase* scrollbar_layer) {
   horizontal_scrollbar_layer_ = scrollbar_layer;
   if (horizontal_scrollbar_layer_)
     horizontal_scrollbar_layer_->set_scroll_layer_id(id());
 }
 
-void LayerImpl::SetVerticalScrollbarLayer(ScrollbarLayerImpl* scrollbar_layer) {
+void LayerImpl::SetVerticalScrollbarLayer(
+    ScrollbarLayerImplBase* scrollbar_layer) {
   vertical_scrollbar_layer_ = scrollbar_layer;
   if (vertical_scrollbar_layer_)
     vertical_scrollbar_layer_->set_scroll_layer_id(id());
 }
 
 static scoped_ptr<base::Value>
 CompositingReasonsAsValue(CompositingReasons reasons) {
   scoped_ptr<base::ListValue> reason_list(new base::ListValue());
 
   if (reasons == kCompositingReasonUnknown) {
@@ skipping 141 matching lines @@
 
 size_t LayerImpl::GPUMemoryUsageInBytes() const { return 0; }
 
 scoped_ptr<base::Value> LayerImpl::AsValue() const {
   scoped_ptr<base::DictionaryValue> state(new base::DictionaryValue());
   AsValueInto(state.get());
   return state.PassAs<base::Value>();
 }
 
 }  // namespace cc