Plumb smooth scrolling in Chromium compositor

cc/layers/layer_impl.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/layers/layer_impl.h"
 
 #include "base/json/json_reader.h"
 #include "base/numerics/safe_conversions.h"
 #include "base/strings/stringprintf.h"
 #include "base/trace_event/trace_event.h"
@@ skipping 1279 matching lines @@
 
 void LayerImpl::SetUpdateRect(const gfx::Rect& update_rect) {
   update_rect_ = update_rect;
   SetNeedsPushProperties();
 }
 
 void LayerImpl::AddDamageRect(const gfx::RectF& damage_rect) {
   damage_rect_ = gfx::UnionRects(damage_rect_, damage_rect);
 }
 
-bool LayerImpl::IsExternalScrollActive() const {
-  return layer_tree_impl_->IsExternalScrollActive();
-}
-
 void LayerImpl::SetCurrentScrollOffset(const gfx::ScrollOffset& scroll_offset) {
   DCHECK(IsActive());
   if (scroll_offset_->SetCurrent(scroll_offset))
     DidUpdateScrollOffset(false);
 }
 
 void LayerImpl::SetCurrentScrollOffsetFromDelegate(
     const gfx::ScrollOffset& scroll_offset) {
   DCHECK(IsActive());
   if (scroll_offset_->SetCurrent(scroll_offset))
@@ skipping 535 matching lines @@
   }
 
   // TODO(enne): the transform needs to come from property trees instead of
   // draw properties.
   gfx::Vector2dF transform_scales = MathUtil::ComputeTransform2dScaleComponents(
       draw_properties().target_space_transform, default_scale);
   return std::max(transform_scales.x(), transform_scales.y());
 }
 
 }  // namespace cc