Scroll with Layers in views::ScrollView

ui/views/view.h

 // Copyright (c) 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 UI_VIEWS_VIEW_H_
 #define UI_VIEWS_VIEW_H_
 
 #include <stddef.h>
 
 #include <algorithm>
@@ skipping 952 matching lines @@
   // Scrolling -----------------------------------------------------------------
   // TODO(beng): Figure out if this can live somewhere other than View, i.e.
   //             closer to ScrollView.
 
   // Scrolls the specified region, in this View's coordinate system, to be
   // visible. View's implementation passes the call onto the parent View (after
   // adjusting the coordinates). It is up to views that only show a portion of
   // the child view, such as Viewport, to override appropriately.
   virtual void ScrollRectToVisible(const gfx::Rect& rect);
 
+  // The closest parent() ScrollView in the hierarchy enclosing this View. Null
+  // if there is none.
+  virtual ScrollView* EnclosingScrollView();
+
   // The following methods are used by ScrollView to determine the amount
   // to scroll relative to the visible bounds of the view. For example, a
   // return value of 10 indicates the scrollview should scroll 10 pixels in
   // the appropriate direction.
   //
   // Each method takes the following parameters:
   //
   // is_horizontal: if true, scrolling is along the horizontal axis, otherwise
   //                the vertical axis.
   // is_positive: if true, scrolling is by a positive amount. Along the
@@ skipping 586 matching lines @@
   // Belongs to this view, but it's reference-counted on some platforms
   // so we can't use a scoped_ptr. It's dereferenced in the destructor.
   NativeViewAccessibility* native_view_accessibility_;
 
   DISALLOW_COPY_AND_ASSIGN(View);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_VIEW_H_