Fix scroll chaining for non-descendants of root scroller.

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 <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 107 matching lines @@
 void LayerImpl::SetDebugInfo(
     std::unique_ptr<base::trace_event::ConvertableToTraceFormat> debug_info) {
   owned_debug_info_ = std::move(debug_info);
   debug_info_ = owned_debug_info_.get();
   SetNeedsPushProperties();
 }
 
 void LayerImpl::DistributeScroll(ScrollState* scroll_state) {
   ScrollTree& scroll_tree = layer_tree_impl()->property_trees()->scroll_tree;
   ScrollNode* scroll_node = scroll_tree.Node(scroll_tree_index());
-  return scroll_tree.DistributeScroll(scroll_node, scroll_state);
-}
-
-void LayerImpl::ApplyScroll(ScrollState* scroll_state) {
-  DCHECK(scroll_state);
-  ScrollNode* node = layer_tree_impl()->property_trees()->scroll_tree.Node(
-      scroll_tree_index());
-  layer_tree_impl()->ApplyScroll(node, scroll_state);
+  scroll_tree.DistributeScroll(scroll_node, scroll_state);
 }
 
 void LayerImpl::SetTransformTreeIndex(int index) {
   transform_tree_index_ = index;
 }
 
 void LayerImpl::SetClipTreeIndex(int index) {
   clip_tree_index_ = index;
 }
 
@@ skipping 961 matching lines @@
            .layer_transforms_should_scale_layer_contents) {
     return default_scale;
   }
 
   gfx::Vector2dF transform_scales = MathUtil::ComputeTransform2dScaleComponents(
       ScreenSpaceTransform(), default_scale);
   return std::max(transform_scales.x(), transform_scales.y());
 }
 
 }  // namespace cc