Revert of Pinch/Zoom Infrastructure & Plumbing CL

cc/trees/layer_tree_host_impl.h

 // Copyright 2011 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_HOST_IMPL_H_
 #define CC_TREES_LAYER_TREE_HOST_IMPL_H_
 
 #include <list>
 #include <set>
 #include <string>
@@ skipping 259 matching lines @@
   const LayerTreeImpl* active_tree() const { return active_tree_.get(); }
   LayerTreeImpl* pending_tree() { return pending_tree_.get(); }
   const LayerTreeImpl* pending_tree() const { return pending_tree_.get(); }
   const LayerTreeImpl* recycle_tree() const { return recycle_tree_.get(); }
   virtual void CreatePendingTree();
   virtual void UpdateVisibleTiles();
   virtual void ActivatePendingTree();
 
   // Shortcuts to layers on the active tree.
   LayerImpl* RootLayer() const;
-  LayerImpl* InnerViewportScrollLayer() const;
-  LayerImpl* OuterViewportScrollLayer() const;
+  LayerImpl* RootScrollLayer() const;
   LayerImpl* CurrentlyScrollingLayer() const;
 
   int scroll_layer_id_when_mouse_over_scrollbar() {
     return scroll_layer_id_when_mouse_over_scrollbar_;
   }
 
   bool IsCurrentlyScrolling() const;
 
   virtual void SetVisible(bool visible);
   bool visible() const { return visible_; }
@@ skipping 166 matching lines @@
   void CreateAndSetRenderer(
       OutputSurface* output_surface,
       ResourceProvider* resource_provider,
       bool skip_gl_renderer);
   void CreateAndSetTileManager(ResourceProvider* resource_provider,
                                ContextProvider* context_provider,
                                bool using_map_image);
   void ReleaseTreeResources();
   void EnforceZeroBudget(bool zero_budget);
 
-  void ScrollViewportBy(gfx::Vector2dF scroll_delta);
   void AnimatePageScale(base::TimeTicks monotonic_time);
   void AnimateScrollbars(base::TimeTicks monotonic_time);
   void AnimateTopControls(base::TimeTicks monotonic_time);
 
   gfx::Vector2dF ScrollLayerWithViewportSpaceDelta(
       LayerImpl* layer_impl,
       float scale_from_viewport_to_screen_space,
       const gfx::PointF& viewport_point,
       const gfx::Vector2dF& viewport_delta);
 
+  void UpdateMaxScrollOffset();
   void TrackDamageForAllSurfaces(
       LayerImpl* root_draw_layer,
       const LayerImplList& render_surface_layer_list);
 
   void UpdateTileManagerMemoryPolicy(const ManagedMemoryPolicy& policy);
 
   // Returns false if the frame should not be displayed. This function should
   // only be called from PrepareToDraw, as DidDrawAllLayers must be called
   // if this helper function is called.
   bool CalculateRenderPasses(FrameData* frame);
@@ skipping 164 matching lines @@
   int id_;
 
   std::set<SwapPromiseMonitor*> swap_promise_monitor_;
 
   DISALLOW_COPY_AND_ASSIGN(LayerTreeHostImpl);
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_HOST_IMPL_H_