Chrome::client() should return a ChromeClient reference.

Source/web/PopupContainer.h

 /*
  * Copyright (c) 2011, Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 111 matching lines @@
 
     // Paint the border.
     void paintBorder(GraphicsContext*, const IntRect&);
 
     // Layout and calculate popup widget size and location and returns it as IntRect.
     IntRect layoutAndCalculateWidgetRect(int targetControlHeight, const IntSize& transformOffset, const IntPoint& popupInitialCoordinate);
 
     void fitToListBox();
 
     // Returns the ChromeClient of the page this popup is associated with.
-    ChromeClient* chromeClient();
+    ChromeClient& chromeClient();
 
     RefPtr<PopupListBox> m_listBox;
     RefPtr<FrameView> m_frameView;
 
     PopupContainerSettings m_settings;
     PopupType m_popupType;
 
     // m_controlPosition contains the transformed position of the
     // <select>/<input> associated with this popup. m_controlSize is the size
     // of the <select>/<input> without transform.
     // The popup menu will be positioned as follows:
     // LTR : If the popup is positioned down it will align with the bottom left
     //       of m_controlPosition (p4)
     //       If the popup is positioned up it will align with the top left of
     //       m_controlPosition (p1)
     // RTL : If the popup is positioned down it will align with the bottom right
     //       of m_controlPosition (p3)
     //       If the popup is positioned up it will align with the top right of
     //       m_controlPosition (p2)
     FloatQuad m_controlPosition;
     IntSize m_controlSize;
 
     // Whether the popup is currently open.
     bool m_popupOpen;
 };
 
 } // namespace WebCore
 
 #endif