Re-Reland: Implement features in NativeViewHostAura for scroll end effect

content/browser/web_contents/aura/constrained_windows_observer.cc

 // Copyright (c) 2013 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.
 
 #include "content/browser/web_contents/aura/constrained_windows_observer.h"
 
 #include "content/browser/renderer_host/render_view_host_factory.h"
 #include "content/browser/renderer_host/render_widget_host_view_aura.h"
 #include "content/browser/renderer_host/render_widget_host_view_aura.h"
 #include "content/browser/web_contents/web_contents_impl.h"
@@ skipping 111 matching lines @@
 
   // We need to undo the above if we were parented to the root window and then
   // got parented to another window. At that point, the code before the ifdef
   // would have stopped watching the root window.
   if (window->GetRootWindow() &&
       parent != window->GetRootWindow() &&
       !window->GetRootWindow()->HasObserver(this)) {
     window->GetRootWindow()->AddObserver(this);
   }
 
-  constrained_parent_ = parent;
+  constrained_parent_ = NULL;
+  if (parent)
+    constrained_parent_ = parent->parent();
 
   if (constrained_parent_) {
     constrained_parent_->AddObserver(this);
     if (constrained_parent_ != window->GetRootWindow()) {
       const aura::Window::Windows& children = constrained_parent_->children();
       for (size_t i = 0; i < children.size(); ++i) {
         if (children[i] != view_->window_)
           children[i]->AddObserver(this);
       }
     }
@@ skipping 45 matching lines @@
         children[i] != exclude &&
         children[i]->IsVisible()) {
       constrained_windows.push_back(children[i]->GetBoundsInRootWindow());
     }
   }
 
   view->UpdateConstrainedWindowRects(constrained_windows);
 }
 
 }  // namespace content