CC Animations: Make LayerAnimationController creation optional

cc/layers/painted_scrollbar_layer.cc

 // Copyright 2013 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/painted_scrollbar_layer.h"
 
 #include <algorithm>
 
 #include "base/auto_reset.h"
 #include "base/basictypes.h"
@@ skipping 13 matching lines @@
 
 namespace cc {
 
 scoped_ptr<LayerImpl> PaintedScrollbarLayer::CreateLayerImpl(
     LayerTreeImpl* tree_impl) {
   return PaintedScrollbarLayerImpl::Create(
       tree_impl, id(), scrollbar_->Orientation());
 }
 
 scoped_refptr<PaintedScrollbarLayer> PaintedScrollbarLayer::Create(
+    const LayerSettings& settings,
     scoped_ptr<Scrollbar> scrollbar,
     int scroll_layer_id) {
   return make_scoped_refptr(
-      new PaintedScrollbarLayer(scrollbar.Pass(), scroll_layer_id));
+      new PaintedScrollbarLayer(settings, scrollbar.Pass(), scroll_layer_id));
 }
 
-PaintedScrollbarLayer::PaintedScrollbarLayer(scoped_ptr<Scrollbar> scrollbar,
+PaintedScrollbarLayer::PaintedScrollbarLayer(const LayerSettings& settings,
+                                             scoped_ptr<Scrollbar> scrollbar,
                                              int scroll_layer_id)
-    : scrollbar_(scrollbar.Pass()),
+    : Layer(settings),
+      scrollbar_(scrollbar.Pass()),
       scroll_layer_id_(scroll_layer_id),
       clip_layer_id_(Layer::INVALID_ID),
       internal_contents_scale_(0.f),
       thumb_thickness_(scrollbar_->ThumbThickness()),
       thumb_length_(scrollbar_->ThumbLength()),
       is_overlay_(scrollbar_->IsOverlay()),
       has_thumb_(scrollbar_->HasThumb()) {
   if (!scrollbar_->IsOverlay())
     SetShouldScrollOnMainThread(true);
 }
@@ skipping 251 matching lines @@
 
   scrollbar_->PaintPart(&skcanvas, part, layer_rect);
   // Make sure that the pixels are no longer mutable to unavoid unnecessary
   // allocation and copying.
   skbitmap.setImmutable();
 
   return UIResourceBitmap(skbitmap);
 }
 
 }  // namespace cc