PlzNavigate: properly execute BeforeUnload on renderer initiated navigations

third_party/WebKit/Source/web/WebLocalFrameImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 669 matching lines @@
     return WebDocument(frame()->document());
 }
 
 WebPerformance WebLocalFrameImpl::performance() const
 {
     if (!frame())
         return WebPerformance();
     return WebPerformance(DOMWindowPerformance::performance(*(frame()->domWindow())));
 }
 
-bool WebLocalFrameImpl::dispatchBeforeUnloadEvent()
-{
-    if (!frame())
-        return true;
-    return frame()->loader().shouldClose();
-}
-
 void WebLocalFrameImpl::dispatchUnloadEvent()
 {
     if (!frame())
         return;
     SubframeLoadingDisabler disabler(frame()->document());
     frame()->loader().dispatchUnloadEvent();
 }
 
 void WebLocalFrameImpl::executeScript(const WebScriptSource& source)
 {
@@ skipping 1131 matching lines @@
 
 void WebLocalFrameImpl::sendPings(const WebURL& destinationURL)
 {
     DCHECK(frame());
     DCHECK(m_contextMenuNode.get());
     Element* anchor = m_contextMenuNode->enclosingLinkEventParentOrSelf();
     if (isHTMLAnchorElement(anchor))
         toHTMLAnchorElement(anchor)->sendPings(destinationURL);
 }
 
+bool WebLocalFrameImpl::dispatchBeforeUnloadEvent(bool* proceed)
+{
+    if (!frame()) {

[dcheng, 2016/05/03 06:51:58]

Do you mind pointing me at the layout test that triggers this condition?

[clamy, 2016/05/03 13:17:09]

It's third_party/WebKit/LayoutTests/fast/events/before-unload-crash.html.

+        *proceed = true;
+        return true;
+    }
+
+    *proceed = frame()->loader().shouldClose();
+    return !!frame();
+}
+
 WebURLRequest WebLocalFrameImpl::requestFromHistoryItem(const WebHistoryItem& item, WebCachePolicy cachePolicy) const
 {
     HistoryItem* historyItem = item;
     ResourceRequest request = FrameLoader::resourceRequestFromHistoryItem(
         historyItem, cachePolicy);
     return WrappedResourceRequest(request);
 }
 
 WebURLRequest WebLocalFrameImpl::requestForReload(WebFrameLoadType loadType,
     const WebURL& overrideUrl) const
@@ skipping 253 matching lines @@
         return WebSandboxFlags::None;
     return static_cast<WebSandboxFlags>(frame()->loader().effectiveSandboxFlags());
 }
 
 void WebLocalFrameImpl::forceSandboxFlags(WebSandboxFlags flags)
 {
     frame()->loader().forceSandboxFlags(static_cast<SandboxFlags>(flags));
 }
 
 } // namespace blink