Remove scroll_clip_layer dependency from viewport layer tracking

cc/trees/layer_tree_impl.h

 // 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.
 
 #ifndef CC_TREES_LAYER_TREE_IMPL_H_
 #define CC_TREES_LAYER_TREE_IMPL_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 200 matching lines @@
   LayerImpl* InnerViewportContainerLayer() const;
   LayerImpl* OuterViewportContainerLayer() const;
   ScrollNode* CurrentlyScrollingNode();
   const ScrollNode* CurrentlyScrollingNode() const;
   int LastScrolledScrollNodeIndex() const;
   void SetCurrentlyScrollingNode(ScrollNode* node);
   void ClearCurrentlyScrollingNode();
 
   void SetViewportLayersFromIds(int overscroll_elasticity_layer,
                                 int page_scale_layer_id,
+                                int inner_viewport_container_layer_id,
+                                int outer_viewport_container_layer_id,
                                 int inner_viewport_scroll_layer_id,
                                 int outer_viewport_scroll_layer_id);
   void ClearViewportLayers();
   LayerImpl* OverscrollElasticityLayer() {
     return LayerById(overscroll_elasticity_layer_id_);
   }
   LayerImpl* PageScaleLayer() { return LayerById(page_scale_layer_id_); }
   void ApplySentScrollAndScaleDeltasFromAbortedCommit();
 
   SkColor background_color() const { return background_color_; }
@@ skipping 289 matching lines @@
   int is_first_frame_after_commit_tracker_;
   LayerImpl* root_layer_for_testing_;
   HeadsUpDisplayLayerImpl* hud_layer_;
   PropertyTrees property_trees_;
   SkColor background_color_;
   bool has_transparent_background_;
 
   int last_scrolled_scroll_node_index_;
   int overscroll_elasticity_layer_id_;
   int page_scale_layer_id_;
+
+  int inner_viewport_container_layer_id_;
+  int outer_viewport_container_layer_id_;
+
   int inner_viewport_scroll_layer_id_;
   int outer_viewport_scroll_layer_id_;
 
   LayerSelection selection_;
 
   scoped_refptr<SyncedProperty<ScaleGroup>> page_scale_factor_;
   float min_page_scale_factor_;
   float max_page_scale_factor_;
 
   float device_scale_factor_;
@@ skipping 80 matching lines @@
   // lifecycle states. See: |LayerTreeLifecycle|.
   LayerTreeLifecycle lifecycle_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(LayerTreeImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_IMPL_H_