Don't send loading completion callbacks for detaching frames.

third_party/WebKit/Source/core/loader/FrameLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights
  * reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved.
  * (http://www.torchmobile.com/)
  * Copyright (C) 2008 Alp Toker <alp@atoker.com>
  * Copyright (C) Research In Motion Limited 2009. All rights reserved.
  * Copyright (C) 2011 Kris Jordan <krisjordan@gmail.com>
  * Copyright (C) 2011 Google Inc. All rights reserved.
@@ skipping 653 matching lines @@
     return false;
 
   // We might have declined to run the load event due to an imminent
   // content-initiated navigation.
   if (!frame->document()->loadEventFinished())
     return false;
 
   // An event might have restarted a child frame.
   if (!allDescendantsAreComplete(frame))
     return false;
+
+  // Don't notify if the frame is being detached.
+  if (frame->isDetaching())
+    return false;
+
   return true;
 }
 
 static bool shouldSendCompleteNotification(LocalFrame* frame,
                                            bool isNavigationHandledByClient) {
   // FIXME: We might have already sent stop notifications and be re-completing.
   if (!frame->isLoading())
     return false;
   // Only send didStopLoading() if there are no navigations in progress at all,
   // whether committed, provisional, or pending.
@@ skipping 1232 matching lines @@
                          m_documentLoader ? m_documentLoader->url() : String());
   return tracedValue;
 }
 
 inline void FrameLoader::takeObjectSnapshot() const {
   TRACE_EVENT_OBJECT_SNAPSHOT_WITH_ID("loading", "FrameLoader", this,
                                       toTracedValue());
 }
 
 }  // namespace blink