Fix AudioEntry destruction order. Add debugging CHECKs for racy shutdown.

content/browser/renderer_host/media/audio_renderer_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/browser/renderer_host/media/audio_renderer_host.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/memory/shared_memory.h"
 #include "base/metrics/histogram.h"
@@ skipping 56 matching lines @@
   virtual void OnError() OVERRIDE;
   virtual void OnDeviceChange(int new_buffer_size, int new_sample_rate)
       OVERRIDE;
 
   AudioRendererHost* const host_;
   const int stream_id_;
 
   // The routing ID of the source render view.
   const int render_view_id_;
 
+  // Shared memory for transmission of the audio data.  Used by |reader_|.
+  const scoped_ptr<base::SharedMemory> shared_memory_;
+
+  // The synchronous reader to be used by |controller_|.
+  const scoped_ptr<media::AudioOutputController::SyncReader> reader_;
+
   // The AudioOutputController that manages the audio stream.
   const scoped_refptr<media::AudioOutputController> controller_;
-
-  // Shared memory for transmission of the audio data.
-  const scoped_ptr<base::SharedMemory> shared_memory_;
-
-  // The synchronous reader to be used by the controller.
-  const scoped_ptr<media::AudioOutputController::SyncReader> reader_;
 };
 
 AudioRendererHost::AudioEntry::AudioEntry(
-    AudioRendererHost* host, int stream_id, int render_view_id,
+    AudioRendererHost* host,
+    int stream_id,
+    int render_view_id,
     const media::AudioParameters& params,
     const std::string& output_device_id,
     scoped_ptr<base::SharedMemory> shared_memory,
     scoped_ptr<media::AudioOutputController::SyncReader> reader)
     : host_(host),
       stream_id_(stream_id),
       render_view_id_(render_view_id),
-      controller_(media::AudioOutputController::Create(
-          host->audio_manager_, this, params, output_device_id, reader.get())),
       shared_memory_(shared_memory.Pass()),
-      reader_(reader.Pass()) {
+      reader_(reader.Pass()),
+      controller_(media::AudioOutputController::Create(host->audio_manager_,
+                                                       this,
+                                                       params,
+                                                       output_device_id,
+                                                       reader_.get())) {
   DCHECK(controller_.get());
 }
 
 AudioRendererHost::AudioEntry::~AudioEntry() {}
 
 ///////////////////////////////////////////////////////////////////////////////
 // AudioRendererHost implementations.
 
 AudioRendererHost::AudioRendererHost(
     int render_process_id,
@@ skipping 347 matching lines @@
 }
 
 AudioRendererHost::AudioEntry* AudioRendererHost::LookupById(int stream_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   AudioEntryMap::const_iterator i = audio_entries_.find(stream_id);
   return i != audio_entries_.end() ? i->second : NULL;
 }
 
 }  // namespace content