First step towards moving AudioDevice from content/ to media/audio.

content/browser/renderer_host/media/audio_input_device_manager.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_input_device_manager.h"
 
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "content/browser/renderer_host/media/audio_input_device_manager_event_handler.h"
 #include "content/public/browser/browser_thread.h"
+#include "media/audio/audio_input_device_ipc.h"
 #include "media/audio/audio_manager_base.h"
 
 using content::BrowserThread;
 
 namespace media_stream {
 
 const int AudioInputDeviceManager::kFakeOpenSessionId = 1;
-const int AudioInputDeviceManager::kInvalidSessionId = 0;
-const char AudioInputDeviceManager::kInvalidDeviceId[] = "";
 
 // Starting id for the first capture session.
 const int kFirstSessionId = AudioInputDeviceManager::kFakeOpenSessionId + 1;
 
 AudioInputDeviceManager::AudioInputDeviceManager(
     media::AudioManager* audio_manager)
     : listener_(NULL),
       next_capture_session_id_(kFirstSessionId),
       audio_manager_(audio_manager) {
 }
@@ skipping 121 matching lines @@
   // called without using Open(), we post default device for test purpose.
   // And we do not store the info for the kFakeOpenSessionId but return
   // the callback immediately.
   if (session_id == kFakeOpenSessionId) {
     event_handler->OnDeviceStarted(session_id,
                                    media::AudioManagerBase::kDefaultDeviceId);
     return;
   }
 
   // Checks if the device has been opened or not.
-  std::string device_id = (devices_.find(session_id) == devices_.end()) ?
-      kInvalidDeviceId : devices_[session_id].unique_id;
+  std::string device_id;
 
   // Adds the event handler to the session if the session has not been started,
-  // otherwise post a |kInvalidDeviceId| to indicate that Start() fails.
-  if (event_handlers_.find(session_id) == event_handlers_.end())
+  // otherwise post an empty |device_id| to indicate that Start() fails.
+  if (event_handlers_.find(session_id) == event_handlers_.end()) {
     event_handlers_.insert(std::make_pair(session_id, event_handler));
-  else
-    device_id = kInvalidDeviceId;
+    if (devices_.find(session_id) != devices_.end())
+      device_id = devices_[session_id].unique_id;
+  }
 
   // Posts a callback through the AudioInputRendererHost to notify the renderer
   // that the device has started.
   event_handler->OnDeviceStarted(session_id, device_id);
 }
 
 void AudioInputDeviceManager::Stop(int session_id) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
   // Erases the event handler referenced by the session_id.
@@ skipping 24 matching lines @@
   if (listener_)
     listener_->Closed(content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE,
                       session_id);
 }
 
 bool AudioInputDeviceManager::IsOnDeviceThread() const {
   return device_loop_->BelongsToCurrentThread();
 }
 
 }  // namespace media_stream