Fix channel lost race in GpuChannelHost

content/common/gpu/client/gpu_channel_host.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/common/gpu/client/gpu_channel_host.h"
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "base/message_loop.h"
 #include "base/message_loop_proxy.h"
@@ skipping 268 matching lines @@
             base::IgnoreResult(&IPC::Listener::OnMessageReceived),
             info.listener,
             message));
   }
 
   return true;
 }
 
 void GpuChannelHost::MessageFilter::OnChannelError() {
   DCHECK(parent_->factory_->IsIOThread());
+
+  // Post the task to signal the GpuChannelHost before the proxies. That way, if
+  // they themselves post a task to recreate the context, they will not try to
+  // re-use this channel host before it has a chance to mark itself lost.
+  MessageLoop* main_loop = parent_->factory_->GetMainLoop();
+  main_loop->PostTask(FROM_HERE,
+                      base::Bind(&GpuChannelHost::OnChannelError, parent_));
   // Inform all the proxies that an error has occurred. This will be reported
   // via OpenGL as a lost context.
   for (ListenerMap::iterator it = listeners_.begin();
        it != listeners_.end();
        it++) {
     const GpuListenerInfo& info = it->second;
     info.loop->PostTask(
         FROM_HERE,
         base::Bind(&IPC::Listener::OnChannelError, info.listener));
   }
 
   listeners_.clear();
-
-  MessageLoop* main_loop = parent_->factory_->GetMainLoop();
-  main_loop->PostTask(FROM_HERE,
-                      base::Bind(&GpuChannelHost::OnChannelError, parent_));
 }