cc: Consolidate LayerList types.

cc/layers/layer_impl.cc

Index: cc/layers/layer_impl.cc
diff --git a/cc/layers/layer_impl.cc b/cc/layers/layer_impl.cc
index da5ca13e3824aeb51a8284e640708aaf36148ea6..34334b19ca84c6b7dfaa8b8beb7e344b3e5346e0 100644
--- a/cc/layers/layer_impl.cc
+++ b/cc/layers/layer_impl.cc
@@ -82,7 +82,7 @@ void LayerImpl::AddChild(scoped_ptr<LayerImpl> child) {
 }
 
 scoped_ptr<LayerImpl> LayerImpl::RemoveChild(LayerImpl* child) {
-  for (ScopedPtrVector<LayerImpl>::iterator it = children_.begin();
+  for (OwnedLayerImplList::iterator it = children_.begin();
        it != children_.end();
        ++it) {
     if (*it == child) {
@@ -110,6 +110,10 @@ void LayerImpl::CreateRenderSurface() {
   draw_properties_.render_target = this;
 }
 
+void LayerImpl::ClearRenderSurface() {
+  draw_properties_.render_surface.reset();
+}
+
 scoped_ptr<SharedQuadState> LayerImpl::CreateSharedQuadState() const {
   scoped_ptr<SharedQuadState> state = SharedQuadState::Create();
   state->SetAll(draw_properties_.target_space_transform,