added back support to speech when ask_user=false

content/browser/speech/speech_recognition_manager_impl.cc

 // Copyright (c) 2013 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/speech/speech_recognition_manager_impl.h"
 
 #include "base/bind.h"
 #include "content/browser/browser_main_loop.h"
 #include "content/browser/renderer_host/media/media_stream_manager.h"
 #include "content/browser/renderer_host/media/media_stream_ui_proxy.h"
 #include "content/browser/speech/google_one_shot_remote_engine.h"
 #include "content/browser/speech/google_streaming_remote_engine.h"
 #include "content/browser/speech/speech_recognition_engine.h"
 #include "content/browser/speech/speech_recognizer_impl.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/resource_context.h"
 #include "content/public/browser/speech_recognition_event_listener.h"
 #include "content/public/browser/speech_recognition_manager_delegate.h"
 #include "content/public/browser/speech_recognition_session_config.h"
 #include "content/public/browser/speech_recognition_session_context.h"
 #include "content/public/common/speech_recognition_error.h"
 #include "content/public/common/speech_recognition_result.h"
 #include "media/audio/audio_manager.h"
+#include "media/audio/audio_manager_base.h"
 
 #if defined(OS_ANDROID)
 #include "content/browser/speech/speech_recognizer_impl_android.h"
 #endif
 
 using base::Callback;
 
 namespace content {
 
 SpeechRecognitionManager* SpeechRecognitionManager::manager_for_tests_;
@@ skipping 526 matching lines @@
   return SESSION_STATE_WAITING_FOR_RESULT;
 }
 
 // ----------- Contract for all the FSM evolution functions below -------------
 //  - Are guaranteed to be executed in the IO thread;
 //  - Are guaranteed to be not reentrant (themselves and each other);
 
 void SpeechRecognitionManagerImpl::SessionStart(const Session& session) {
   DCHECK_EQ(primary_session_id_, session.id);
   const MediaStreamDevices& devices = session.context.devices;
-  DCHECK_EQ(1u, devices.size());
-  DCHECK_EQ(MEDIA_DEVICE_AUDIO_CAPTURE, devices.front().type);
+  std::string device_id;
+  if (devices.empty()) {
+    // From the ask_user=false path, use the default device.
+    // TODO(xians): Abort the session after we do not need to support this path
+    // anymore.
+    device_id = media::AudioManagerBase::kDefaultDeviceId;
+  } else {
+    // From the ask_user=true path, use the selected device.
+    DCHECK_EQ(1u, devices.size());
+    DCHECK_EQ(MEDIA_DEVICE_AUDIO_CAPTURE, devices.front().type);
+    device_id = devices.front().id;
+  }
 
-  session.recognizer->StartRecognition(devices.front().id);
+  session.recognizer->StartRecognition(device_id);
 }
 
 void SpeechRecognitionManagerImpl::SessionAbort(const Session& session) {
   if (primary_session_id_ == session.id)
     primary_session_id_ = kSessionIDInvalid;
   DCHECK(session.recognizer.get());
   session.recognizer->AbortRecognition();
 }
 
 void SpeechRecognitionManagerImpl::SessionStopAudioCapture(
@@ skipping 77 matching lines @@
 
 SpeechRecognitionManagerImpl::Session::Session()
   : id(kSessionIDInvalid),
     listener_is_active(true) {
 }
 
 SpeechRecognitionManagerImpl::Session::~Session() {
 }
 
 }  // namespace content