Remove a bunch of fixed position dead code.

sky/engine/public/platform/WebLayer.h

 /*
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 171 matching lines @@
 
     virtual void setNonFastScrollableRegion(const WebVector<WebRect>&) = 0;
     virtual WebVector<WebRect> nonFastScrollableRegion() const = 0;
 
     virtual void setTouchEventHandlerRegion(const WebVector<WebRect>&) = 0;
     virtual WebVector<WebRect> touchEventHandlerRegion() const = 0;
 
     virtual void setIsContainerForFixedPositionLayers(bool) = 0;
     virtual bool isContainerForFixedPositionLayers() const = 0;
 
-    // This function sets layer position constraint. The constraint will be used
-    // to adjust layer position during threaded scrolling.
-    virtual void setPositionConstraint(const WebLayerPositionConstraint&) = 0;
-    virtual WebLayerPositionConstraint positionConstraint() const = 0;
-
     // The scroll client is notified when the scroll position of the WebLayer
     // changes. Only a single scroll client can be set for a WebLayer at a time.
     // The WebLayer does not take ownership of the scroll client, and it is the
     // responsibility of the client to reset the layer's scroll client before
     // deleting the scroll client.
     virtual void setScrollClient(WebLayerScrollClient*) = 0;
 
     // Forces this layer to use a render surface. There is no benefit in doing
     // so, but this is to facilitate benchmarks and tests.
     virtual void setForceRenderSurface(bool) = 0;
 
     // True if the layer is not part of a tree attached to a WebLayerTreeView.
     virtual bool isOrphan() const = 0;
 
     virtual void setWebLayerClient(WebLayerClient*) = 0;
 };
 
 } // namespace blink
 
 #endif // WebLayer_h