Fix renderer crashes when frame gets detached while injectng user scripts.

content/renderer/render_view_impl.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/render_view_impl.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/auto_reset.h"
@@ skipping 3680 matching lines @@
   WebDataSource* ds = frame->dataSource();
   DocumentState* document_state = DocumentState::FromDataSource(ds);
   document_state->set_finish_document_load_time(Time::Now());
 
   Send(new ViewHostMsg_DocumentLoadedInFrame(routing_id_, frame->identifier()));
 
   FOR_EACH_OBSERVER(RenderViewObserver, observers_,
                     DidFinishDocumentLoad(frame));
 
   // Check whether we have new encoding name.
-  UpdateEncoding(frame, frame->view()->pageEncoding().utf8());
+  if (frame->view())

[dcheng, 2014/02/07 16:53:37]

Might be good to add a comment on why you need to check this, e.g.
// RenderViewObservers can run Javascript that removes |frame| so it may no
longer have a view.

+    UpdateEncoding(frame, frame->view()->pageEncoding().utf8());
 }
 
 void RenderViewImpl::didHandleOnloadEvents(WebFrame* frame) {
   if (webview()->mainFrame() == frame) {
     Send(new ViewHostMsg_DocumentOnLoadCompletedInMainFrame(routing_id_,
                                                             page_id_));
   }
 }
 
 void RenderViewImpl::didFailLoad(WebFrame* frame, const WebURLError& error) {
@@ skipping 2529 matching lines @@
   for (size_t i = 0; i < icon_urls.size(); i++) {
     WebURL url = icon_urls[i].iconURL();
     if (!url.isEmpty())
       urls.push_back(FaviconURL(url,
                                 ToFaviconType(icon_urls[i].iconType())));
   }
   SendUpdateFaviconURL(urls);
 }
 
 }  // namespace content