Rename cc property tree node owner_id to owning_layer_id.

cc/trees/scroll_node.h

 // Copyright 2016 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_TREES_SCROLL_NODE_H_
 #define CC_TREES_SCROLL_NODE_H_
 
 #include "cc/base/cc_export.h"
 #include "cc/output/filter_operations.h"
 #include "ui/gfx/geometry/size.h"
 
 namespace base {
 namespace trace_event {
 class TracedValue;
 }  // namespace trace_event
 }  // namespace base
 
 namespace cc {
 
 struct CC_EXPORT ScrollNode {
   ScrollNode();
   ScrollNode(const ScrollNode& other);
 
+  // The node index of this node in the scroll tree node vector.
   int id;
+  // The node index of the parent node in the scroll tree node vector.
   int parent_id;
 
   // The layer id that corresponds to the layer contents that are scrolled.
   // Unlike |id|, this id is stable across frames that don't change the
   // composited layer list.
-  int owner_id;
+  int owning_layer_id;
 
   // This is used for subtrees that should not be scrolled independently. For
   // example, when there is a layer that is not scrollable itself but is inside
   // a scrolling layer.
   bool scrollable;
 
   uint32_t main_thread_scrolling_reasons;
   bool contains_non_fast_scrollable_region;
 
   // Size of the clipped area, not including non-overlay scrollbars. Overlay
@@ skipping 17 matching lines @@
   ElementId element_id;
   int transform_id;
 
   bool operator==(const ScrollNode& other) const;
   void AsValueInto(base::trace_event::TracedValue* value) const;
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_SCROLL_NODE_H_