Fixes focus traversal bug

ui/views/widget/widget_delegate.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_WIDGET_WIDGET_DELEGATE_H_
 #define UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 141 matching lines @@
   // the default window manager. In some cases, like panel, we would like to
   // manage the positions by ourselves.
   virtual bool WillProcessWorkAreaChange() const;
 
   // Returns true if window has a hit-test mask.
   virtual bool WidgetHasHitTestMask() const;
 
   // Provides the hit-test mask if HasHitTestMask above returns true.
   virtual void GetWidgetHitTestMask(gfx::Path* mask) const;
 
+  // Returns true if focus should advance to the top level widget when
+  // tab/shift-tab is hit and on the last/first focusable view. Default returns
+  // false, which means tab/shift-tab never advance to the top level Widget.
+  virtual bool ShouldAdvanceFocusToTopLevelWidget() const;
+
   // Returns true if event handling should descend into |child|.
   // |location| is in terms of the Window.
   virtual bool ShouldDescendIntoChildForEventHandling(
       gfx::NativeView child,
       const gfx::Point& location);
 
   // Populates |panes| with accessible panes in this window that can
   // be cycled through with keyboard focus.
   virtual void GetAccessiblePanes(std::vector<View*>* panes) {}
 
@@ skipping 20 matching lines @@
   virtual Widget* GetWidget() OVERRIDE;
   virtual const Widget* GetWidget() const OVERRIDE;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(WidgetDelegateView);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_WIDGET_WIDGET_DELEGATE_H_