Don't stop the documentLoader on navigations.

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.
  *
  * Redistribution and use in source and binary forms, with or without
@@ skipping 921 matching lines @@
     if (document->hasActiveParser())
         return false;
     return true;
 }
 
 bool FrameLoader::checkLoadCompleteForThisFrame()
 {
     ASSERT(client()->hasWebView());
     RefPtr<LocalFrame> protect(m_frame);
 
+    bool allChildrenAreDoneLoading = true;
+    for (LocalFrame* child = m_frame->tree().firstChild(); child; child = child->tree().nextSibling())
+        allChildrenAreDoneLoading &= child->loader().checkLoadCompleteForThisFrame();
+
     if (m_state == FrameStateProvisional && m_provisionalDocumentLoader) {
         const ResourceError& error = m_provisionalDocumentLoader->mainDocumentError();
         if (error.isNull())
             return false;
         RefPtr<DocumentLoader> loader = m_provisionalDocumentLoader;
         client()->dispatchDidFailProvisionalLoad(error);
         if (loader != m_provisionalDocumentLoader)
             return false;
         m_provisionalDocumentLoader->detachFromFrame();
         m_provisionalDocumentLoader = nullptr;
         m_progressTracker->progressCompleted();
         m_state = FrameStateComplete;
         return true;
     }
 
-    bool allChildrenAreDoneLoading = true;
-    for (LocalFrame* child = m_frame->tree().firstChild(); child; child = child->tree().nextSibling())
-        allChildrenAreDoneLoading &= child->loader().checkLoadCompleteForThisFrame();
     if (!allChildrenAreDoneLoading)
         return false;
 
     if (m_state == FrameStateComplete)
         return true;
     if (m_provisionalDocumentLoader || !m_documentLoader)
         return false;
     if (!isDocumentDoneLoading(m_frame->document()) && !m_inStopAllLoaders)
         return false;
 
@@ skipping 314 matching lines @@
         m_policyDocumentLoader->setOverrideEncoding(m_documentLoader->overrideEncoding());
 
     // stopAllLoaders can detach the LocalFrame, so protect it.
     RefPtr<LocalFrame> protect(m_frame);
     if ((!m_policyDocumentLoader->shouldContinueForNavigationPolicy(request) || !shouldClose()) && m_policyDocumentLoader) {
         m_policyDocumentLoader->detachFromFrame();
         m_policyDocumentLoader = nullptr;
         return;
     }
 
-    // A new navigation is in progress, so don't clear the history's provisional item.
-    stopAllLoaders();
+    if (m_provisionalDocumentLoader) {
+        m_provisionalDocumentLoader->stopLoading();
+        if (m_provisionalDocumentLoader)
+            m_provisionalDocumentLoader->detachFromFrame();
+        m_provisionalDocumentLoader = nullptr;
+    }
+    m_checkTimer.stop();
 
     // <rdar://problem/6250856> - In certain circumstances on pages with multiple frames, stopAllLoaders()
     // might detach the current FrameLoader, in which case we should bail on this newly defunct load.
     if (!m_frame->page() || !m_policyDocumentLoader)
         return;
 
     if (isLoadingMainFrame())
         m_frame->page()->inspectorController().resume();
     m_frame->navigationScheduler().cancel();
 
@@ skipping 133 matching lines @@
 {
     SandboxFlags flags = m_forcedSandboxFlags;
     if (LocalFrame* parentFrame = m_frame->tree().parent())
         flags |= parentFrame->document()->sandboxFlags();
     if (FrameOwner* frameOwner = m_frame->ownerElement())
         flags |= frameOwner->sandboxFlags();
     return flags;
 }
 
 } // namespace WebCore