Fix a crash in WebRtcRtpDumpHandler.

chrome/browser/media/webrtc_rtp_dump_writer.cc

 // Copyright 2014 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 "chrome/browser/media/webrtc_rtp_dump_writer.h"
 
 #include "base/big_endian.h"
 #include "base/file_util.h"
 #include "base/logging.h"
 #include "content/public/browser/browser_thread.h"
@@ skipping 429 matching lines @@
   if (incoming && context.type == RTP_DUMP_BOTH) {
     FlushBuffer(false,
                 true,
                 base::Bind(&WebRtcRtpDumpWriter::OnDumpEnded,
                            weak_ptr_factory_.GetWeakPtr(),
                            context,
                            false));
     return;
   }
 
+  // This object might be deleted after running the callback.
   context.callback.Run(context.incoming_succeeded, context.outgoing_succeeded);
 }