[content shell] add support for dumping frame load callbacks

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/bind.h"
@@ skipping 3235 matching lines @@
     return;
 
   if (enable_pinch)
     webview()->setPageScaleFactorLimits(1, 4);
   else
     webview()->setPageScaleFactorLimits(1, 1);
 }
 
 void RenderViewImpl::didStartProvisionalLoad(WebFrame* frame) {
   WebDataSource* ds = frame->provisionalDataSource();
+
+  // In fast/loader/stop-provisional-loads.html, we abort the load before this
+  // callback is invoked.
+  if (!ds)
+    return;
+
   DocumentState* document_state = DocumentState::FromDataSource(ds);
 
   // We should only navigate to swappedout:// when is_swapped_out_ is true.
   CHECK((ds->request().url() != GURL(kSwappedOutURL)) ||
         is_swapped_out_) << "Heard swappedout:// when not swapped out.";
 
   // Update the request time if WebKit has better knowledge of it.
   if (document_state->request_time().is_null()) {
     double event_time = ds->triggeringEventTime();
     if (event_time != 0.0)
@@ skipping 3240 matching lines @@
 }
 #endif
 
 void RenderViewImpl::OnReleaseDisambiguationPopupDIB(
     TransportDIB::Handle dib_handle) {
   TransportDIB* dib = TransportDIB::CreateWithHandle(dib_handle);
   RenderProcess::current()->ReleaseTransportDIB(dib);
 }
 
 }  // namespace content