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

cc/trees/tree_synchronizer.cc

Index: cc/trees/tree_synchronizer.cc
diff --git a/cc/trees/tree_synchronizer.cc b/cc/trees/tree_synchronizer.cc
index f307257ff05819fb35b16d65cddf4780cea09f74..1dfc354dca3fbdde51f278a3bddcfbdd8f277abf 100644
--- a/cc/trees/tree_synchronizer.cc
+++ b/cc/trees/tree_synchronizer.cc
@@ -11,8 +11,8 @@
 #include "cc/input/scrollbar.h"
 #include "cc/layers/layer.h"
 #include "cc/layers/layer_impl.h"
-#include "cc/layers/scrollbar_layer.h"
-#include "cc/layers/scrollbar_layer_impl.h"
+#include "cc/layers/scrollbar_layer_impl_base.h"
+#include "cc/layers/scrollbar_layer_interface.h"
 
 namespace cc {
 
@@ -154,18 +154,19 @@ void UpdateScrollbarLayerPointersRecursiveInternal(
     return;
 
   RawPtrLayerImplMap::const_iterator iter =
-      new_layers->find(scrollbar_layer->id());
-  ScrollbarLayerImpl* scrollbar_layer_impl =
-      iter != new_layers->end() ? static_cast<ScrollbarLayerImpl*>(iter->second)
-                               : NULL;
-  iter = new_layers->find(scrollbar_layer->scroll_layer_id());
+      new_layers->find(layer->id());
+  ScrollbarLayerImplBase* scrollbar_layer_impl =
+      iter != new_layers->end()
+          ? static_cast<ScrollbarLayerImplBase*>(iter->second)
+          : NULL;
+  iter = new_layers->find(scrollbar_layer->ScrollLayerId());
   LayerImpl* scroll_layer_impl =
       iter != new_layers->end() ? iter->second : NULL;
 
   DCHECK(scrollbar_layer_impl);
   DCHECK(scroll_layer_impl);
 
-  if (scrollbar_layer->Orientation() == HORIZONTAL)
+  if (scrollbar_layer->orientation() == HORIZONTAL)
     scroll_layer_impl->SetHorizontalScrollbarLayer(scrollbar_layer_impl);
   else
     scroll_layer_impl->SetVerticalScrollbarLayer(scrollbar_layer_impl);
@@ -173,14 +174,15 @@ void UpdateScrollbarLayerPointersRecursiveInternal(
 
 void UpdateScrollbarLayerPointersRecursive(const RawPtrLayerImplMap* new_layers,
                                            Layer* layer) {
-  UpdateScrollbarLayerPointersRecursiveInternal<Layer, ScrollbarLayer>(
+  UpdateScrollbarLayerPointersRecursiveInternal<Layer, ScrollbarLayerInterface>(
       new_layers, layer);
 }
 
 void UpdateScrollbarLayerPointersRecursive(const RawPtrLayerImplMap* new_layers,
                                            LayerImpl* layer) {
-  UpdateScrollbarLayerPointersRecursiveInternal<LayerImpl, ScrollbarLayerImpl>(
-      new_layers, layer);
+  UpdateScrollbarLayerPointersRecursiveInternal<
+      LayerImpl,
+      ScrollbarLayerImplBase>(new_layers, layer);
 }
 
 // static