views/examples: Make SingleSplitViewExample a listener of SingleSplitView control.

views/examples/single_split_view_example.h

 // Copyright (c) 2011 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 VIEWS_EXAMPLES_SINGLE_SPLIT_VIEW_EXAMPLE_H_
 #define VIEWS_EXAMPLES_SINGLE_SPLIT_VIEW_EXAMPLE_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
+#include "views/controls/single_split_view_listener.h"
 #include "views/examples/example_base.h"
 
-namespace views {
-class SingleSplitView;
-}
-
 namespace examples {
 
-class SingleSplitViewExample : public ExampleBase {
+class SingleSplitViewExample : public ExampleBase,
+                               public views::SingleSplitViewListener {
  public:
   explicit SingleSplitViewExample(ExamplesMain* main);
   virtual ~SingleSplitViewExample();
 
   // Overridden from ExampleBase:
   virtual void CreateExampleView(views::View* container) OVERRIDE;
 
  private:
+  virtual bool SplitHandleMoved(views::SingleSplitView* sender) OVERRIDE;
+
   views::SingleSplitView* single_split_view_;
 
   DISALLOW_COPY_AND_ASSIGN(SingleSplitViewExample);
 };
 
 }  // namespace examples
 
 #endif  // VIEWS_EXAMPLES_SINGLE_SPLIT_VIEW_EXAMPLE_H_