Fix crash caused by DCHECK global pointer for --single-process model

content/renderer/media/aec_dump_message_filter.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 "content/renderer/media/aec_dump_message_filter.h"
 
 #include "base/message_loop/message_loop_proxy.h"
 #include "content/common/media/aec_dump_messages.h"
 #include "content/renderer/media/webrtc_logging.h"
 #include "ipc/ipc_logging.h"
 #include "ipc/ipc_sender.h"
 
 namespace {
 const int kInvalidDelegateId = -1;
 }
 
 namespace content {
 
 AecDumpMessageFilter* AecDumpMessageFilter::g_filter = NULL;
 
 AecDumpMessageFilter::AecDumpMessageFilter(
     const scoped_refptr<base::MessageLoopProxy>& io_message_loop,
     const scoped_refptr<base::MessageLoopProxy>& main_message_loop)
     : sender_(NULL),
       delegate_id_counter_(0),
       io_message_loop_(io_message_loop),
       main_message_loop_(main_message_loop) {
-  DCHECK(!g_filter);
   g_filter = this;
 }
 
 AecDumpMessageFilter::~AecDumpMessageFilter() {
   DCHECK_EQ(g_filter, this);

[jrummell, 2015/03/02 23:54:14]

If the DCHECK in the constructor needs to be removed, why aren't these? I would
assume that if there is 2 creations, then one of the these would fail.

   g_filter = NULL;
 }
 
 // static
 scoped_refptr<AecDumpMessageFilter> AecDumpMessageFilter::Get() {
   return g_filter;
 }
 
 void AecDumpMessageFilter::AddDelegate(
     AecDumpMessageFilter::AecDumpDelegate* delegate) {
@@ skipping 138 matching lines @@
   DCHECK(main_message_loop_->BelongsToCurrentThread());
   for (DelegateMap::iterator it = delegates_.begin();
        it != delegates_.end(); ++it) {
     if (it->second == delegate)
       return it->first;
   }
   return kInvalidDelegateId;
 }
 
 }  // namespace content