Avoid a possible race between entry deletion and a command, in the event a...

chrome/browser/renderer_host/audio_renderer_host.cc

 // Copyright (c) 2011 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/renderer_host/audio_renderer_host.h"
 
 #include "base/metrics/histogram.h"
 #include "base/process.h"
 #include "base/shared_memory.h"
 #include "chrome/browser/renderer_host/audio_sync_reader.h"
@@ skipping 442 matching lines @@
   SendErrorMessage(entry->render_view_id, entry->stream_id);
   CloseAndDeleteStream(entry);
 }
 
 AudioRendererHost::AudioEntry* AudioRendererHost::LookupById(
     int route_id, int stream_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   AudioEntryMap::iterator i = audio_entries_.find(
       AudioEntryId(route_id, stream_id));
-  if (i != audio_entries_.end())
+  if (i != audio_entries_.end() && !i->second->pending_close)
     return i->second;
   return NULL;
 }
 
 AudioRendererHost::AudioEntry* AudioRendererHost::LookupByController(
     media::AudioOutputController* controller) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   // Iterate the map of entries.
   // TODO(hclam): Implement a faster look up method.
   for (AudioEntryMap::iterator i = audio_entries_.begin();
        i != audio_entries_.end(); ++i) {
-    if (controller == i->second->controller.get())
+    if (!i->second->pending_close && controller == i->second->controller.get())
       return i->second;
   }
   return NULL;
 }