[cc] Make LayerImpls point at LayerTreeImpl instead of LTHI

cc/scrollbar_layer.cc

 // Copyright 2012 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/scrollbar_layer.h"
 
 #include "base/basictypes.h"
 #include "base/debug/trace_event.h"
 #include "cc/layer_painter.h"
 #include "cc/layer_tree_host.h"
 #include "cc/resource_update_queue.h"
 #include "cc/scrollbar_layer_impl.h"
 #include "ui/gfx/rect_conversions.h"
 #include <public/WebRect.h>
 
 using WebKit::WebRect;
 
 namespace cc {
 
-scoped_ptr<LayerImpl> ScrollbarLayer::createLayerImpl(LayerTreeHostImpl* hostImpl)
+scoped_ptr<LayerImpl> ScrollbarLayer::createLayerImpl(LayerTreeImpl* treeImpl)
 {
-    return ScrollbarLayerImpl::create(hostImpl, id()).PassAs<LayerImpl>();
+    return ScrollbarLayerImpl::create(treeImpl, id()).PassAs<LayerImpl>();
 }
 
 scoped_refptr<ScrollbarLayer> ScrollbarLayer::create(scoped_ptr<WebKit::WebScrollbar> scrollbar, WebKit::WebScrollbarThemePainter painter, scoped_ptr<WebKit::WebScrollbarThemeGeometry> geometry, int scrollLayerId)
 {
     return make_scoped_refptr(new ScrollbarLayer(scrollbar.Pass(), painter, geometry.Pass(), scrollLayerId));
 }
 
 ScrollbarLayer::ScrollbarLayer(scoped_ptr<WebKit::WebScrollbar> scrollbar, WebKit::WebScrollbarThemePainter painter, scoped_ptr<WebKit::WebScrollbarThemeGeometry> geometry, int scrollLayerId)
     : m_scrollbar(scrollbar.Pass())
     , m_painter(painter)
@@ skipping 271 matching lines @@
         updatePart(m_foreTrackUpdater.get(), m_foreTrack.get(), contentRect, queue, stats);
 
     // Consider the thumb to be at the origin when painting.
     WebKit::WebRect thumbRect = m_geometry->thumbRect(m_scrollbar.get());
     gfx::Rect originThumbRect = scrollbarLayerRectToContentRect(gfx::Rect(0, 0, thumbRect.width, thumbRect.height));
     if (!originThumbRect.IsEmpty())
         updatePart(m_thumbUpdater.get(), m_thumb.get(), originThumbRect, queue, stats);
 }
 
 }  // namespace cc