Views: Draw Textfield selected text in gray when top-level Widget loses focus.

ui/views/focus/focus_manager.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_FOCUS_FOCUS_MANAGER_H_
 #define UI_VIEWS_FOCUS_FOCUS_MANAGER_H_
 
 #include <list>
 #include <map>
 #include <memory>
@@ skipping 101 matching lines @@
 // This interface should be implemented by classes that want to be notified when
 // the focus is about to change.  See the Add/RemoveFocusChangeListener methods.
 class VIEWS_EXPORT FocusChangeListener {
  public:
   // No change to focus state has occurred yet when this function is called.
   virtual void OnWillChangeFocus(View* focused_before, View* focused_now) = 0;
 
   // Called after focus state has changed.
   virtual void OnDidChangeFocus(View* focused_before, View* focused_now) = 0;
 
+  virtual void OnFocusManagerDestroying() {}
+
  protected:
   virtual ~FocusChangeListener() {}
 };
 
 class VIEWS_EXPORT FocusManager {
  public:
   // The reason why the focus changed.
   enum FocusChangeReason {
     // The focus changed because the user traversed focusable views using
     // keys like Tab or Shift+Tab.
@@ skipping 251 matching lines @@
   // access is enabled.
   // Default value is false.
   bool keyboard_accessible_;
 
   DISALLOW_COPY_AND_ASSIGN(FocusManager);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_FOCUS_FOCUS_MANAGER_H_