Fix for 75024. r=danm, sr=ben

content/events/src/nsDOMEvent.cpp

@@ -149,7 +149,7 @@ nsDOMEvent::nsDOMEvent(nsIPresContext* aPresContext, nsEvent* aEvent, const nsAR
       mEvent = PR_NEWZAP(nsEvent);
       mEvent->eventStructType = NS_EVENT;
     }
-    else if (eventType.EqualsIgnoreCase("MutationEvent")) {
+    else if (eventType.EqualsIgnoreCase("MutationEvents")) {
       mEvent = PR_NEWZAP(nsMutationEvent);
       mEvent->eventStructType = NS_MUTATION_EVENT;
     }
@@ -1393,9 +1393,14 @@ nsDOMEvent::GetScriptObject(nsIScriptContext *aContext, void** aScriptObject)
   nsresult res = NS_OK;
 
   if (nsnull == mScriptObject) {
-    nsISupports *supports = (nsISupports *)(nsIDOMMouseEvent *)this;
-
-    res = NS_NewScriptKeyEvent(aContext, supports, nsnull, (void**)&mScriptObject);
+    if (mEvent && mEvent->eventStructType == NS_MUTATION_EVENT) {
+      nsISupports *supports = (nsISupports *)(nsIDOMMutationEvent *)this;
+      res = NS_NewScriptMutationEvent(aContext, supports, nsnull, (void**)&mScriptObject);
+    }
+    else {
+      nsISupports *supports = (nsISupports *)(nsIDOMMouseEvent *)this;
+      res = NS_NewScriptKeyEvent(aContext, supports, nsnull, (void**)&mScriptObject);
+    }
   }
   *aScriptObject = mScriptObject;
 

content/events/src/nsDOMMutationEvent.cpp

@@ -43,9 +43,9 @@ class nsDOMMutationEvent : public nsIDOMMutationEvent, public nsDOMEvent
 
 nsDOMMutationEvent::nsDOMMutationEvent(nsIPresContext* aPresContext,
                                        nsEvent* aEvent)
-:nsDOMEvent(aPresContext, aEvent, NS_LITERAL_STRING("MutationEvent")) 
+:nsDOMEvent(aPresContext, aEvent, NS_LITERAL_STRING("MutationEvents")) 
 {  
-  nsMutationEvent* mutation = (nsMutationEvent*)aEvent;
+  nsMutationEvent* mutation = (nsMutationEvent*)mEvent;
   SetTarget(mutation->mTarget);
 }
 
@@ -60,6 +60,7 @@ NS_INTERFACE_MAP_BEGIN(nsDOMMutationEvent)
   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsIDOMEvent, nsIDOMMutationEvent)
   NS_INTERFACE_MAP_ENTRY(nsIPrivateDOMEvent)
   NS_INTERFACE_MAP_ENTRY(nsIDOMMutationEvent)
+  NS_INTERFACE_MAP_ENTRY(nsIScriptObjectOwner)
 NS_INTERFACE_MAP_END
 
 NS_IMETHODIMP

content/events/src/nsEventListenerManager.cpp

@@ -2091,13 +2091,13 @@ nsresult nsEventListenerManager::CreateEvent(nsIPresContext* aPresContext,
 {
   nsAutoString str(aEventType);
   if (!aEvent && !str.EqualsIgnoreCase("MouseEvent") && !str.EqualsIgnoreCase("KeyEvent") &&
-      !str.EqualsIgnoreCase("HTMLEvent") && !str.EqualsIgnoreCase("MutationEvent") &&
+      !str.EqualsIgnoreCase("HTMLEvent") && !str.EqualsIgnoreCase("MutationEvents") &&
       !str.EqualsIgnoreCase("Event")) {
     return NS_ERROR_DOM_NOT_SUPPORTED_ERR;
   }
 
   if ((aEvent && aEvent->eventStructType == NS_MUTATION_EVENT) ||
-      (!aEvent && str.EqualsIgnoreCase("MutationEvent")))
+      (!aEvent && str.EqualsIgnoreCase("MutationEvents")))
     return NS_NewDOMMutationEvent(aDOMEvent, aPresContext, aEvent);
   return NS_NewDOMUIEvent(aDOMEvent, aPresContext, aEventType, aEvent);
 }