nsMutationEvent(PRUint32 msg = 0, PRUint8 structType = NS_MUTATION_EVENT) : nsEvent(msg, structType),
nsMutationEvent(PRBool isTrusted, PRUint32 msg) : nsEvent(isTrusted, msg, NS_MUTATION_EVENT),
  nsMutationEvent(PRUint32 msg = 0, PRUint8 structType = NS_MUTATION_EVENT)    : nsEvent(msg, structType),      mAttrChange(0)  {    flags |= NS_EVENT_FLAG_CANT_CANCEL;  }