First part of work to move V8 binding integrity off of vtables.

Source/WebCore/Modules/mediastream/RTCDTMFToneChangeEvent.cpp

Index: Source/WebCore/Modules/mediastream/RTCDTMFToneChangeEvent.cpp
diff --git a/Source/WebCore/Modules/mediastream/RTCDTMFToneChangeEvent.cpp b/Source/WebCore/Modules/mediastream/RTCDTMFToneChangeEvent.cpp
index bc9b67182bdb913d2e58fdfe0d349fcc0d25827b..99563c97c2bccbab34c008fc5f358cfadfa5f824 100644
--- a/Source/WebCore/Modules/mediastream/RTCDTMFToneChangeEvent.cpp
+++ b/Source/WebCore/Modules/mediastream/RTCDTMFToneChangeEvent.cpp
@@ -50,18 +50,21 @@ PassRefPtr<RTCDTMFToneChangeEvent> RTCDTMFToneChangeEvent::create(const AtomicSt
 
 RTCDTMFToneChangeEvent::RTCDTMFToneChangeEvent()
 {
+    ScriptWrappable::init(this);
 }
 
 RTCDTMFToneChangeEvent::RTCDTMFToneChangeEvent(const String& tone)
     : Event(eventNames().tonechangeEvent, false, false)
     , m_tone(tone)
 {
+    ScriptWrappable::init(this);
 }
 
 RTCDTMFToneChangeEvent::RTCDTMFToneChangeEvent(const RTCDTMFToneChangeEventInit& initializer)
     : Event(eventNames().tonechangeEvent, initializer)
     , m_tone(initializer.tone)
 {
+    ScriptWrappable::init(this);
 }
 
 RTCDTMFToneChangeEvent::~RTCDTMFToneChangeEvent()