--- a/dom/xhr/XMLHttpRequestMainThread.cpp
+++ b/dom/xhr/XMLHttpRequestMainThread.cpp
@@ -1267,26 +1267,23 @@ XMLHttpRequestMainThread::GetLoadGroup()
   if (doc) {
     return doc->GetDocumentLoadGroup();
   }
 
   return nullptr;
 }
 
 nsresult
-XMLHttpRequestMainThread::CreateReadystatechangeEvent(nsIDOMEvent** aDOMEvent)
+XMLHttpRequestMainThread::FireReadystatechangeEvent()
 {
   RefPtr<Event> event = NS_NewDOMEvent(this, nullptr, nullptr);
-  event.forget(aDOMEvent);
-
-  (*aDOMEvent)->InitEvent(kLiteralString_readystatechange, false, false);
-
+  event->InitEvent(kLiteralString_readystatechange, false, false);
   // We assume anyone who managed to call CreateReadystatechangeEvent is trusted
-  (*aDOMEvent)->SetTrusted(true);
-
+  event->SetTrusted(true);
+  DispatchDOMEvent(nullptr, event, nullptr, nullptr);
   return NS_OK;
 }
 
 void
 XMLHttpRequestMainThread::DispatchProgressEvent(DOMEventTargetHelper* aTarget,
                                                 const ProgressEventType aType,
                                                 bool aLengthComputable,
                                                 int64_t aLoaded, int64_t aTotal)
@@ -3114,21 +3111,17 @@ XMLHttpRequestMainThread::ChangeState(St
     mProgressTimerIsActive = false;
     mProgressNotifier->Cancel();
   }
 
 
   if (aBroadcast && (!mFlagSynchronous ||
                      aState == State::opened ||
                      aState == State::done)) {
-    nsCOMPtr<nsIDOMEvent> event;
-    rv = CreateReadystatechangeEvent(getter_AddRefs(event));
-    NS_ENSURE_SUCCESS(rv, rv);
-
-    DispatchDOMEvent(nullptr, event, nullptr, nullptr);
+    rv = FireReadystatechangeEvent();
   }
 
   return rv;
 }
 
 /////////////////////////////////////////////////////
 // nsIChannelEventSink methods:
 //

--- a/dom/xhr/XMLHttpRequestMainThread.h
+++ b/dom/xhr/XMLHttpRequestMainThread.h
@@ -515,19 +515,19 @@ public:
   }
 
   // We need a GetInterface callable from JS for chrome JS
   virtual void
   GetInterface(JSContext* aCx, nsIJSID* aIID,
                JS::MutableHandle<JS::Value> aRetval,
                ErrorResult& aRv) override;
 
-  // This creates a trusted readystatechange event, which is not cancelable and
+  // This fires a trusted readystatechange event, which is not cancelable and
   // doesn't bubble.
-  nsresult CreateReadystatechangeEvent(nsIDOMEvent** aDOMEvent);
+  nsresult FireReadystatechangeEvent();
   void DispatchProgressEvent(DOMEventTargetHelper* aTarget,
                              const ProgressEventType aType,
                              bool aLengthComputable,
                              int64_t aLoaded, int64_t aTotal);
 
   // Dispatch the "progress" event on the XHR or XHR.upload object if we've
   // received data since the last "progress" event. Also dispatches
   // "uploadprogress" as needed.