Revert of Pinch/Zoom Infrastructure & Plumbing CL (https://codereview.chromium.org/23983047/)

Reason for revert:
Broke Linux ASAN Tests (3) bot.

Original issue's description:
> Pinch/Zoom Infrastructure & Plumbing CL
> 
> This CL supplies the necessary changes to CC to support the
> inner/outer viewport model for pinch-zoom and fixed-position
> elements. The specification for these changes is contained in
> the document "Layer-based Solution for Pinch Zoom / Fixed
> Position".
> 
> It incorporates a change to how scrollbar parameters are
> computed (removes the notion of max_scroll_offset as a
> quantity set be the embedder, and instead inferred from the
> relative sizes of a clip layer w.r.t. the scroll layer).
> 
> Scrollbars are generalized so that a layer may have more than
> two scrollbars, and the parameters of the scrollbar are set
> w.r.t. the sizes and positions of a clip and a scroll layer.
> Further, changes to the scrip/scroll layer automatically
> notify any attached scrollbars.
> 
> The CL also removes existing references to root_scroll_layer
> from LTH, LTI and LTHI and replaces them with either
> Inner/OuterViewportScrollLayer (dual-layer operation only
> exists at present if the --enable-pinch-virtual-viewport flag
> is specified, otherwise behavior is unchanged).
> 
> Logic is added to (i) combine scroll offsets for the two
> viewports before passing it to the embedder, and (ii)
> splitting any offsets received from the embedder
> appropriately between the two viewports.
> 
> This CL relies on https://codereview.chromium.org/138453004/
> for changes in Blink to support it.
> 
> BUG=148816
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=246812
> 
> R=aelias@chromium.org, enne@chromium.org, joi@chromium.org, piman@chromium.org, sky@chromium.org
> 
> Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=247684

TBR=enne@chromium.org,aelias@chromium.org,joi@chromium.org,sky@chromium.org,piman@chromium.org,tony@chromium.org,wjmaclean@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=148816

Review URL: https://codereview.chromium.org/135183016

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@247688 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 6 insertions, 16 deletions

diff --git a/cc/trees/layer_tree_impl.h b/cc/trees/layer_tree_impl.h
index 81a8992..7c4479d 100644
--- a/cc/trees/layer_tree_impl.h
+++ b/cc/trees/layer_tree_impl.h
@@ -34,7 +34,6 @@ class ContextProvider;
 class DebugRectHistory;
 class FrameRateCounter;
 class HeadsUpDisplayLayerImpl;
-class LayerScrollOffsetDelegateProxy;
 class LayerTreeDebugState;
 class LayerTreeHostImpl;
 class LayerTreeImpl;
@@ -114,24 +113,18 @@ class CC_EXPORT LayerTreeImpl {
     hud_layer_ = layer_impl;
   }
 
-  LayerImpl* InnerViewportScrollLayer() const;
-  // This function may return NULL, it is the caller's responsibility to check.
-  LayerImpl* OuterViewportScrollLayer() const;
-  gfx::Vector2dF TotalScrollOffset() const;
-  gfx::Vector2dF TotalMaxScrollOffset() const;
-  gfx::Vector2dF TotalScrollDelta() const;
-
+  LayerImpl* RootScrollLayer() const;
   LayerImpl* RootContainerLayer() const;
   LayerImpl* CurrentlyScrollingLayer() const;
   void SetCurrentlyScrollingLayer(LayerImpl* layer);
   void ClearCurrentlyScrollingLayer();
-  float VerticalAdjust(const LayerImpl* layer) const;
 
+  void FindRootScrollLayer();
+  void UpdateMaxScrollOffset();
   void SetViewportLayersFromIds(int page_scale_layer_id,
                                 int inner_viewport_scroll_layer_id,
                                 int outer_viewport_scroll_layer_id);
   void ClearViewportLayers();
-  LayerImpl* page_scale_layer() { return page_scale_layer_; }
   void ApplySentScrollAndScaleDeltasFromAbortedCommit();
   void ApplyScrollDeltasSinceBeginMainFrame();
 
@@ -214,8 +207,6 @@ class CC_EXPORT LayerTreeImpl {
 
   void SetRootLayerScrollOffsetDelegate(
       LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate);
-  void UpdateScrollOffsetDelegate();
-  gfx::Vector2dF GetDelegatedScrollOffset(LayerImpl* layer);
 
   // Call this function when you expect there to be a swap buffer.
   // See swap_promise.h for how to use SwapPromise.
@@ -240,18 +231,17 @@ class CC_EXPORT LayerTreeImpl {
  protected:
   explicit LayerTreeImpl(LayerTreeHostImpl* layer_tree_host_impl);
 
+  void UpdateSolidColorScrollbars();
+
   void UpdateRootScrollLayerSizeDelta();
 
   LayerTreeHostImpl* layer_tree_host_impl_;
   int source_frame_number_;
   scoped_ptr<LayerImpl> root_layer_;
   HeadsUpDisplayLayerImpl* hud_layer_;
+  LayerImpl* root_scroll_layer_;
   LayerImpl* currently_scrolling_layer_;
   LayerScrollOffsetDelegate* root_layer_scroll_offset_delegate_;
-  scoped_ptr<LayerScrollOffsetDelegateProxy>
-      inner_viewport_scroll_delegate_proxy_;
-  scoped_ptr<LayerScrollOffsetDelegateProxy>
-      outer_viewport_scroll_delegate_proxy_;
   SkColor background_color_;
   bool has_transparent_background_;