Revert of cc: Make PaintedScrollbarLayer not use ContentsScalingLayer

cc/test/fake_painted_scrollbar_layer.h

 // 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.
 
 #ifndef CC_TEST_FAKE_PAINTED_SCROLLBAR_LAYER_H_
 #define CC_TEST_FAKE_PAINTED_SCROLLBAR_LAYER_H_
 
 #include "base/memory/scoped_ptr.h"
 #include "cc/layers/painted_scrollbar_layer.h"
 #include "cc/test/fake_scrollbar.h"
@@ skipping 22 matching lines @@
   // For unit tests
   UIResourceId track_resource_id() {
     return PaintedScrollbarLayer::track_resource_id();
   }
   UIResourceId thumb_resource_id() {
     return PaintedScrollbarLayer::thumb_resource_id();
   }
   FakeScrollbar* fake_scrollbar() {
     return fake_scrollbar_;
   }
-  using PaintedScrollbarLayer::UpdateInternalContentScale;
   using PaintedScrollbarLayer::UpdateThumbAndTrackGeometry;
 
  private:
   FakePaintedScrollbarLayer(FakeScrollbar* fake_scrollbar,
                             int scrolling_layer_id);
   ~FakePaintedScrollbarLayer() override;
 
   int update_count_;
   size_t push_properties_count_;
   FakeScrollbar* fake_scrollbar_;
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_FAKE_PAINTED_SCROLLBAR_LAYER_H_