Add support for onvoiceschanged event.

Source/modules/speech/DOMWindowSpeechSynthesis.cpp

 /*
  * Copyright (C) 2012 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 14 matching lines @@
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 
 #include "config.h"
 #include "modules/speech/DOMWindowSpeechSynthesis.h"
 
 #include "core/frame/DOMWindow.h"
+#include "core/frame/Frame.h"
 #include "wtf/PassRefPtr.h"
 
 namespace WebCore {
 
 DOMWindowSpeechSynthesis::DOMWindowSpeechSynthesis(DOMWindow* window)
     : DOMWindowProperty(window->frame())
 {
 }
 
 DOMWindowSpeechSynthesis::~DOMWindowSpeechSynthesis()
@@ skipping 18 matching lines @@
 
 // static
 SpeechSynthesis* DOMWindowSpeechSynthesis::speechSynthesis(DOMWindow* window)
 {
     return DOMWindowSpeechSynthesis::from(window)->speechSynthesis();
 }
 
 SpeechSynthesis* DOMWindowSpeechSynthesis::speechSynthesis()
 {
     if (!m_speechSynthesis && frame())
-        m_speechSynthesis = SpeechSynthesis::create();
+        m_speechSynthesis = SpeechSynthesis::create(frame()->domWindow()->executionContext());
     return m_speechSynthesis.get();
 }
 
 } // namespace WebCore