Begin adding support for tab mirroring via the MediaStream audio/video capturing

content/browser/renderer_host/media/media_stream_manager.cc

Index: content/browser/renderer_host/media/media_stream_manager.cc
diff --git a/content/browser/renderer_host/media/media_stream_manager.cc b/content/browser/renderer_host/media/media_stream_manager.cc
index 8194fde724332595de1996e35f27e6c6f4aa7e41..b8a8eef32fcc39470a7015f253be75b1dc445846 100644
--- a/content/browser/renderer_host/media/media_stream_manager.cc
+++ b/content/browser/renderer_host/media/media_stream_manager.cc
@@ -11,6 +11,7 @@
 #include "base/logging.h"
 #include "base/rand_util.h"
 #include "base/win/scoped_com_initializer.h"
+#include "content/browser/browser_main_loop.h"
 #include "content/browser/renderer_host/media/audio_input_device_manager.h"
 #include "content/browser/renderer_host/media/media_stream_device_settings.h"
 #include "content/browser/renderer_host/media/media_stream_requester.h"
@@ -47,10 +48,8 @@ static std::string RandomLabel() {
 // Helper to verify if a media stream type is part of options or not.
 static bool Requested(const StreamOptions& options,
                       MediaStreamType stream_type) {
-  return (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE &&
-          options.video) ||
-         (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE &&
-          options.audio);
+  return (options.audio_type == stream_type ||
+          options.video_type == stream_type);
 }
 
 DeviceThread::DeviceThread(const char* name)
@@ -90,12 +89,10 @@ struct MediaStreamManager::DeviceRequest {
 
   DeviceRequest()
       : requester(NULL),
-        state(content::NUM_MEDIA_STREAM_DEVICE_TYPES, STATE_NOT_REQUESTED),
+        state(content::NUM_MEDIA_TYPES, STATE_NOT_REQUESTED),
         type(GENERATE_STREAM),
         render_process_id(-1),
         render_view_id(-1) {
-    options.audio = false;
-    options.video = false;
   }
 
   DeviceRequest(MediaStreamRequester* requester,
@@ -105,7 +102,7 @@ struct MediaStreamManager::DeviceRequest {
                 const GURL& request_security_origin)
       : requester(requester),
         options(request_options),
-        state(content::NUM_MEDIA_STREAM_DEVICE_TYPES, STATE_NOT_REQUESTED),
+        state(content::NUM_MEDIA_TYPES, STATE_NOT_REQUESTED),
         type(GENERATE_STREAM),
         render_process_id(render_process_id),
         render_view_id(render_view_id),
@@ -123,8 +120,7 @@ struct MediaStreamManager::DeviceRequest {
   int render_view_id;
   GURL security_origin;
   std::string requested_device_id;
-  StreamDeviceInfoArray audio_devices;
-  StreamDeviceInfoArray video_devices;
+  StreamDeviceInfoArray devices;
 };
 
 MediaStreamManager::EnumerationCache::EnumerationCache()
@@ -134,13 +130,10 @@ MediaStreamManager::EnumerationCache::EnumerationCache()
 MediaStreamManager::EnumerationCache::~EnumerationCache() {
 }
 
-MediaStreamManager::MediaStreamManager(
-    AudioInputDeviceManager* audio_input_device_manager,
-    VideoCaptureManager* video_capture_manager)
+MediaStreamManager::MediaStreamManager()
     : ALLOW_THIS_IN_INITIALIZER_LIST(
           device_settings_(new MediaStreamDeviceSettings(this))),
-      audio_input_device_manager_(audio_input_device_manager),
-      video_capture_manager_(video_capture_manager),
+      audio_manager_(NULL),
       monitoring_started_(false),
       io_loop_(NULL) {
   memset(active_enumeration_ref_count_, 0,
@@ -153,20 +146,6 @@ MediaStreamManager::~MediaStreamManager() {
   DCHECK(!io_loop_);
 }
 
-VideoCaptureManager* MediaStreamManager::video_capture_manager() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  DCHECK(video_capture_manager_);
-  EnsureDeviceThreadAndListener();
-  return video_capture_manager_;
-}
-
-AudioInputDeviceManager* MediaStreamManager::audio_input_device_manager() {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  DCHECK(audio_input_device_manager_);
-  EnsureDeviceThreadAndListener();
-  return audio_input_device_manager_;
-}
-
 void MediaStreamManager::GenerateStream(MediaStreamRequester* requester,
                                         int render_process_id,
                                         int render_view_id,
@@ -190,6 +169,45 @@ void MediaStreamManager::GenerateStream(MediaStreamRequester* requester,
                                               security_origin);
 }
 
+void MediaStreamManager::GenerateStreamForDevice(
+    MediaStreamRequester* requester, int render_process_id, int render_view_id,
+    const StreamOptions& options, const std::string& device_id,
+    const GURL& security_origin, std::string* label) {
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  // Create a new request based on options.
+  AddRequest(DeviceRequest(requester, options,
+                           render_process_id, render_view_id,
+                           security_origin),
+             label);
+  DeviceRequest& request = requests_[*label];
+
+  // Get user confirmation to use the capture device.
+  device_settings_->RequestCaptureDeviceUsage(*label,
+                                              render_process_id,
+                                              render_view_id,
+                                              options,
+                                              security_origin);
+  // TODO(miu): We should ask the device manager whether a device with id
+  // |device_id| actually exists.  Note that no such MediaStreamProvider API for
+  // this currently exists.  Also, we don't have a user-friendly device name for
+  // the infobar UI.
+  if (content::IsAudioMediaType(options.audio_type)) {
+    request.state[options.audio_type] = DeviceRequest::STATE_PENDING_APPROVAL;
+    device_settings_->AvailableDevices(
+        *label, options.audio_type, StreamDeviceInfoArray(
+            1, StreamDeviceInfo(options.audio_type, device_id, device_id,
+                                false)));
+  }
+  if (content::IsVideoMediaType(options.video_type)) {
+    request.state[options.video_type] = DeviceRequest::STATE_PENDING_APPROVAL;
+    device_settings_->AvailableDevices(
+        *label, options.video_type, StreamDeviceInfoArray(
+            1, StreamDeviceInfo(options.video_type, device_id, device_id,
+                                false)));
+  }
+}
+
 void MediaStreamManager::CancelGenerateStream(const std::string& label) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
@@ -197,21 +215,19 @@ void MediaStreamManager::CancelGenerateStream(const std::string& label) {
   if (it != requests_.end()) {
     // The request isn't complete.
     if (!RequestDone(it->second)) {
-      DeviceRequest* request = &(it->second);
-      if (request->state[content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE] ==
-          DeviceRequest::STATE_OPENING) {
-        for (StreamDeviceInfoArray::iterator it =
-             request->audio_devices.begin(); it != request->audio_devices.end();
-             ++it) {
-          audio_input_device_manager()->Close(it->session_id);
+      DeviceRequest& request = it->second;
+      for (int i = content::MEDIA_NO_SERVICE + 1; i < content::NUM_MEDIA_TYPES;
+           ++i) {
+        const MediaStreamType stream_type = static_cast<MediaStreamType>(i);
+        if (request.state[stream_type] != DeviceRequest::STATE_OPENING) {
+          continue;
         }
-      }
-      if (request->state[content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE] ==
-          DeviceRequest::STATE_OPENING) {
-        for (StreamDeviceInfoArray::iterator it =
-             request->video_devices.begin(); it != request->video_devices.end();
-             ++it) {
-          video_capture_manager()->Close(it->session_id);
+        for (StreamDeviceInfoArray::const_iterator device_it =
+                 request.devices.begin();
+             device_it != request.devices.end(); ++device_it) {
+          if (device_it->stream_type == stream_type) {
+            GetDeviceManager(stream_type)->Close(device_it->session_id);
+          }
         }
       }
       requests_.erase(it);
@@ -231,15 +247,10 @@ void MediaStreamManager::StopGeneratedStream(const std::string& label) {
       StopEnumerateDevices(label);
       return;
     }
-    for (StreamDeviceInfoArray::iterator audio_it =
-         it->second.audio_devices.begin();
-         audio_it != it->second.audio_devices.end(); ++audio_it) {
-      audio_input_device_manager()->Close(audio_it->session_id);
-    }
-    for (StreamDeviceInfoArray::iterator video_it =
-         it->second.video_devices.begin();
-         video_it != it->second.video_devices.end(); ++video_it) {
-      video_capture_manager()->Close(video_it->session_id);
+    for (StreamDeviceInfoArray::const_iterator device_it =
+             it->second.devices.begin();
+         device_it != it->second.devices.end(); ++device_it) {
+      GetDeviceManager(device_it->stream_type)->Close(device_it->session_id);
     }
     if (it->second.type == DeviceRequest::GENERATE_STREAM &&
         RequestDone(it->second)) {
@@ -257,18 +268,20 @@ void MediaStreamManager::EnumerateDevices(
     const GURL& security_origin,
     std::string* label) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  DCHECK(type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE ||
-         type == content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE);
+  DCHECK(type == content::MEDIA_AUDIO_DEVICE_CAPTURE ||
+         type == content::MEDIA_VIDEO_DEVICE_CAPTURE);
 
   // Create a new request.
   StreamOptions options;
   EnumerationCache* cache = NULL;
-  if (type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE) {
-    options.audio = true;
+  if (type == content::MEDIA_AUDIO_DEVICE_CAPTURE) {
+    options.audio_type = type;
     cache = &audio_enumeration_cache_;
-  } else {
-    options.video = true;
+  } else if (type == content::MEDIA_VIDEO_DEVICE_CAPTURE) {
+    options.video_type = type;
     cache = &video_enumeration_cache_;
+  } else {
+    NOTREACHED();
   }

[wjia(left Chromium), 2012/09/07 14:11:36]

Based on the DCHECK at the beginning of this function, after this line, "cache"
should be non-NULL pointer. It seems you are trying to extend it to cover other
cases, e.g., "type" could be MEDIA_TAB_*_CAPTURE. That will be confusing. It's
better to make the change only when it's needed.

[miu, 2012/09/07 23:14:28]

(This was just left over from an earlier revision of the file.)

For safety, on a Release build, I've just put in a return statement after the
NOTREACHED().  Then, the rest of the code in this method is reverted back to the
way it was originally (i.e., it assumes cache is not NULL).

On 2012/09/07 14:11:36, wjia wrote:

 
   DeviceRequest new_request(requester, options,
@@ -277,10 +290,10 @@ void MediaStreamManager::EnumerateDevices(
                             security_origin);
   new_request.type = DeviceRequest::ENUMERATE_DEVICES;
 
-  if (cache->valid) {
+  if (cache && cache->valid) {
     // Cached device list of this type exists. Just send it out.
     new_request.state[type] = DeviceRequest::STATE_REQUESTED;
-    AddRequest(&new_request, label);
+    AddRequest(new_request, label);
     // Need to post a task since the requester won't have label till
     // this function returns.
     BrowserThread::PostTask(BrowserThread::IO,
@@ -289,7 +302,9 @@ void MediaStreamManager::EnumerateDevices(
                    base::Unretained(this), cache, *label));
   } else {
     StartEnumeration(&new_request, label);
-    StartMonitoring();
+    if (cache) {
+      StartMonitoring();
+    }
   }
 }
 
@@ -315,13 +330,19 @@ void MediaStreamManager::OpenDevice(
     const GURL& security_origin,
     std::string* label) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  DCHECK(type == content::MEDIA_AUDIO_DEVICE_CAPTURE ||
+         type == content::MEDIA_VIDEO_DEVICE_CAPTURE);

[wjia(left Chromium), 2012/09/07 14:11:36]

Thanks for adding DCHECK!

 
   // Create a new request.
   StreamOptions options;
-  if (type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE)
-    options.audio = true;
-  else
-    options.video = true;
+  if (content::IsAudioMediaType(type)) {
+    options.audio_type = type;
+  } else if (content::IsVideoMediaType(type)) {
+    options.video_type = type;
+  } else {

[wjia(left Chromium), 2012/09/07 14:11:36]

NOTREACHED() for this branch?

[miu, 2012/09/07 23:14:28]

Done.

+    LOG(FATAL) << "Cannot handle request for MediaStreamType " << type;
+    return;
+  }
 
   DeviceRequest new_request(requester, options,
                             render_process_id,
@@ -373,30 +394,24 @@ void MediaStreamManager::StartEnumeration(
     std::string* label) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
-  MediaStreamType stream_type = content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE;
-  if (Requested(new_request->options, stream_type)) {
-    new_request->state[stream_type] = DeviceRequest::STATE_REQUESTED;
-    DCHECK_GE(active_enumeration_ref_count_[stream_type], 0);
-    if (!active_enumeration_ref_count_[stream_type]) {
-      ++active_enumeration_ref_count_[stream_type];
-      GetDeviceManager(stream_type)->EnumerateDevices();
-    }
-  }
-  stream_type = content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE;
-  if (Requested(new_request->options, stream_type)) {
-    new_request->state[stream_type] = DeviceRequest::STATE_REQUESTED;
-    DCHECK_GE(active_enumeration_ref_count_[stream_type], 0);
-    if (!active_enumeration_ref_count_[stream_type]) {
-      ++active_enumeration_ref_count_[stream_type];
-      GetDeviceManager(stream_type)->EnumerateDevices();
+  for (int i = content::MEDIA_NO_SERVICE + 1; i < content::NUM_MEDIA_TYPES;
+       ++i) {
+    const MediaStreamType stream_type = static_cast<MediaStreamType>(i);
+    if (Requested(new_request->options, stream_type)) {
+      new_request->state[stream_type] = DeviceRequest::STATE_REQUESTED;
+      DCHECK_GE(active_enumeration_ref_count_[stream_type], 0);
+      if (active_enumeration_ref_count_[stream_type] == 0) {
+        ++active_enumeration_ref_count_[stream_type];
+        GetDeviceManager(stream_type)->EnumerateDevices();
+      }
     }
   }
 
-  AddRequest(new_request, label);
+  AddRequest(*new_request, label);
 }
 
 void MediaStreamManager::AddRequest(
-    DeviceRequest* new_request,
+    const DeviceRequest& new_request,
     std::string* label) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
@@ -406,27 +421,51 @@ void MediaStreamManager::AddRequest(
     request_label = RandomLabel();
   } while (requests_.find(request_label) != requests_.end());
 
-  requests_.insert(std::make_pair(request_label, *new_request));
+  requests_.insert(std::make_pair(request_label, new_request));
 
   (*label) = request_label;
 }
 
-void MediaStreamManager::EnsureDeviceThreadAndListener() {
+void MediaStreamManager::EnsureDeviceManagerStarted(
+    MediaStreamType stream_type) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  if (device_thread_.get())
-    return;
 
-  device_thread_.reset(new DeviceThread("MediaStreamDeviceThread"));
-  CHECK(device_thread_->Start());
+  if (!device_thread_.get()) {
+    device_thread_.reset(new DeviceThread("MediaStreamDeviceThread"));
+    CHECK(device_thread_->Start());
+  }
 
-  audio_input_device_manager_->Register(this,
-                                        device_thread_->message_loop_proxy());
-  video_capture_manager_->Register(this, device_thread_->message_loop_proxy());
+  if (!device_manager_[stream_type]) {
+    switch (stream_type) {
+      case content::MEDIA_AUDIO_DEVICE_CAPTURE:
+      case content::MEDIA_TAB_AUDIO_CAPTURE:
+        if (!audio_manager_) {
+          audio_manager_ = content::BrowserMainLoop::GetAudioManager();

[wjia(left Chromium), 2012/09/07 14:11:36]

Injecting an audio_manager in ctor can remove the need of accessing
BrowserMainLoop. That helps unit tests and doesn't need SetAudioManager().

[miu, 2012/09/07 23:14:28]

Done.

+        }
+        device_manager_[stream_type] =
+            new media_stream::AudioInputDeviceManager(audio_manager_,
+                                                      stream_type);
+        break;
+      case content::MEDIA_VIDEO_DEVICE_CAPTURE:
+      case content::MEDIA_TAB_VIDEO_CAPTURE:
+        device_manager_[stream_type] =
+            new media_stream::VideoCaptureManager(stream_type);
+        break;
+      default:
+        LOG(FATAL) << "Cannot create device manager for invalid or "
+                   << "unsupported MediaStreamType " << stream_type;
+        return;
+    }
+    device_manager_[stream_type]->Register(
+        this, device_thread_->message_loop_proxy());
+  }
 
   // We want to be notified of IO message loop destruction to delete the thread
   // and the device managers.
-  io_loop_ = MessageLoop::current();
-  io_loop_->AddDestructionObserver(this);
+  if (!io_loop_) {
+    io_loop_ = MessageLoop::current();
+    io_loop_->AddDestructionObserver(this);
+  }
 }
 
 void MediaStreamManager::Opened(MediaStreamType stream_type,
@@ -439,17 +478,11 @@ void MediaStreamManager::Opened(MediaStreamType stream_type,
   std::string label;
   for (DeviceRequests::iterator request_it = requests_.begin();
        request_it != requests_.end() && request == NULL; ++request_it) {
-    if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE) {
-      devices = &(request_it->second.audio_devices);
-    } else if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE) {
-      devices = &(request_it->second.video_devices);
-    } else {
-      NOTREACHED();
-    }
-
+    devices = &(request_it->second.devices);
     for (StreamDeviceInfoArray::iterator device_it = devices->begin();
          device_it != devices->end(); ++device_it) {
-      if (device_it->session_id == capture_session_id) {
+      if (device_it->stream_type == stream_type &&
+          device_it->session_id == capture_session_id) {
         // We've found the request.
         device_it->in_use = true;
         label = request_it->first;
@@ -469,6 +502,8 @@ void MediaStreamManager::Opened(MediaStreamType stream_type,
   // they are.
   for (StreamDeviceInfoArray::iterator device_it = devices->begin();
        device_it != devices->end(); ++device_it) {
+    if (device_it->stream_type != stream_type)
+      continue;
     if (device_it->in_use == false) {
       // Wait for more devices to be opened before we're done.
       return;
@@ -481,17 +516,36 @@ void MediaStreamManager::Opened(MediaStreamType stream_type,
     return;
   }
 
+  // Partition the array of devices into audio vs video.

[wjia(left Chromium), 2012/09/07 14:11:36]

This portion of code (partitioning the devices into audio and video) needs to be
done only if (request->type == DeviceRequest::GENERATE_STREAM). It can be moved
into DeviceRequest::GENERATE_STREAM branch of the switch below.

[miu, 2012/09/07 23:14:28]

Done.

+  StreamDeviceInfoArray audio_devices, video_devices;
+  for (StreamDeviceInfoArray::const_iterator device_it = devices->begin();
+       device_it != devices->end(); ++device_it) {
+    if (content::IsAudioMediaType(device_it->stream_type)) {
+      audio_devices.push_back(*device_it);
+    } else if (content::IsVideoMediaType(device_it->stream_type)) {
+      video_devices.push_back(*device_it);
+    } else {
+      NOTREACHED();
+    }
+  }
+
   switch (request->type) {
     case DeviceRequest::OPEN_DEVICE:
-      request->requester->DeviceOpened(label, (*devices)[0]);
+      if (content::IsAudioMediaType(stream_type)) {
+        request->requester->DeviceOpened(label, audio_devices.front());
+      } else if (content::IsVideoMediaType(stream_type)) {
+        request->requester->DeviceOpened(label, video_devices.front());
+      } else {
+        NOTREACHED();
+      }

[wjia(left Chromium), 2012/09/07 14:11:36]

This change is not needed for DeviceRequest::OPEN_DEVICE. "devices" can be used
directly without partitioning.

[miu, 2012/09/07 23:14:28]

Done.

       break;
     case DeviceRequest::GENERATE_STREAM:
-      request->requester->StreamGenerated(label, request->audio_devices,
-                                          request->video_devices);
+      request->requester->StreamGenerated(label, audio_devices, video_devices);
       NotifyObserverDevicesOpened(request);
       break;
     default:
       NOTREACHED();
+      break;
   }
 }
 
@@ -504,11 +558,11 @@ void MediaStreamManager::DevicesEnumerated(
     MediaStreamType stream_type, const StreamDeviceInfoArray& devices) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
 
-  // Only cache device list when there is EnumerateDevices request, since
+  // Only cache the device list when there is an EnumerateDevices request, since
   // other requests don't turn on device monitoring.
   bool need_update_clients = false;
   EnumerationCache* cache =
-      (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE ?
+      (stream_type == content::MEDIA_AUDIO_DEVICE_CAPTURE ?
        &audio_enumeration_cache_ : &video_enumeration_cache_);
   if (HasEnumerationRequest(stream_type) &&
       (!cache->valid ||
@@ -543,8 +597,9 @@ void MediaStreamManager::DevicesEnumerated(
           request.requester->DevicesEnumerated(*it, devices);
         break;
       case DeviceRequest::OPEN_DEVICE:
+        DCHECK(!request.requested_device_id.empty());
         for (StreamDeviceInfoArray::const_iterator device_it = devices.begin();
-             device_it != devices.end(); device_it++) {
+             device_it != devices.end(); ++device_it) {
           if (request.requested_device_id == device_it->device_id) {
             StreamDeviceInfo device = *device_it;
             device.in_use = false;
@@ -552,16 +607,14 @@ void MediaStreamManager::DevicesEnumerated(
                 GetDeviceManager(device_it->stream_type)->Open(device);
             request.state[device_it->stream_type] =
                 DeviceRequest::STATE_OPENING;
-            if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE)
-              request.audio_devices.push_back(device);
-            else
-              request.video_devices.push_back(device);
+            request.devices.push_back(device);
             break;
           }
         }
         break;
       default:
         device_settings_->AvailableDevices(*it, stream_type, devices);
+        break;
     }
   }
   label_list.clear();
@@ -574,52 +627,58 @@ void MediaStreamManager::Error(MediaStreamType stream_type,
                                MediaStreamProviderError error) {
   // Find the device for the error call.
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
   for (DeviceRequests::iterator it = requests_.begin(); it != requests_.end();
        ++it) {
-    StreamDeviceInfoArray* devices = NULL;
-    if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE) {
-      devices = &(it->second.audio_devices);
-    } else if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE) {
-      devices = &(it->second.video_devices);
-    } else {
-      NOTREACHED();
-    }
+    StreamDeviceInfoArray& devices = it->second.devices;
 
-    int device_idx = 0;
-    for (StreamDeviceInfoArray::iterator device_it = devices->begin();
-         device_it != devices->end(); ++device_it, ++device_idx) {
-      if (device_it->session_id == capture_session_id) {
-        // We've found the failing device. Find the error case:
-        if (it->second.state[stream_type] == DeviceRequest::STATE_DONE) {
-          // 1. Already opened -> signal device failure and close device.
-          //    Use device_idx to signal which of the devices encountered an
-          //    error.
-          if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE) {
-            it->second.requester->AudioDeviceFailed(it->first, device_idx);
-          } else if (stream_type ==
-                     content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE) {
-            it->second.requester->VideoDeviceFailed(it->first, device_idx);
-          }
-          GetDeviceManager(stream_type)->Close(capture_session_id);
-          // We don't erase the devices here so that we can update the UI
-          // properly in StopGeneratedStream().
-          it->second.state[stream_type] = DeviceRequest::STATE_ERROR;
+    int audio_device_idx = -1;
+    int video_device_idx = -1;
+    for (StreamDeviceInfoArray::iterator device_it = devices.begin();
+         device_it != devices.end(); ++device_it) {
+      if (content::IsAudioMediaType(device_it->stream_type)) {
+        ++audio_device_idx;
+      } else if (content::IsVideoMediaType(device_it->stream_type)) {
+        ++video_device_idx;
+      } else {
+        NOTREACHED();
+        continue;
+      }
+      if (device_it->stream_type != stream_type ||
+          device_it->session_id != capture_session_id) {
+        continue;
+      }
+      // We've found the failing device. Find the error case:
+      if (it->second.state[stream_type] == DeviceRequest::STATE_DONE) {
+        // 1. Already opened -> signal device failure and close device.
+        //    Use device_idx to signal which of the devices encountered an
+        //    error.
+        if (content::IsAudioMediaType(stream_type)) {
+          it->second.requester->AudioDeviceFailed(it->first, audio_device_idx);
+        } else if (content::IsVideoMediaType(stream_type)) {
+          it->second.requester->VideoDeviceFailed(it->first, video_device_idx);
         } else {
-          // Request is not done, devices are not opened in this case.
-          if ((it->second.audio_devices.size() +
-               it->second.video_devices.size()) <= 1) {
-            // 2. Device not opened and no other devices for this request ->
-            //    signal stream error and remove the request.
-            it->second.requester->StreamGenerationFailed(it->first);
-            requests_.erase(it);
-          } else {
-            // 3. Not opened but other devices exists for this request -> remove
-            //    device from list, but don't signal an error.
-            devices->erase(device_it);
-          }
+          NOTREACHED();
+          return;
+        }
+        GetDeviceManager(stream_type)->Close(capture_session_id);
+        // We don't erase the devices here so that we can update the UI
+        // properly in StopGeneratedStream().
+        it->second.state[stream_type] = DeviceRequest::STATE_ERROR;
+      } else {
+        // Request is not done, devices are not opened in this case.
+        if (devices.size() <= 1) {
+          // 2. Device not opened and no other devices for this request ->
+          //    signal stream error and remove the request.
+          it->second.requester->StreamGenerationFailed(it->first);
+          requests_.erase(it);
+        } else {
+          // 3. Not opened but other devices exists for this request -> remove
+          //    device from list, but don't signal an error.
+          devices.erase(device_it);  // NOTE: This invalidates device_it!
         }
-        return;
       }
+      return;
     }
   }
 }
@@ -628,53 +687,55 @@ void MediaStreamManager::DevicesAccepted(const std::string& label,
                                          const StreamDeviceInfoArray& devices) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
   DeviceRequests::iterator request_it = requests_.find(label);
-  if (request_it != requests_.end()) {
-    if (devices.empty()) {
-      // No available devices or user didn't accept device usage.
-      request_it->second.requester->StreamGenerationFailed(request_it->first);
-      requests_.erase(request_it);
-      return;
-    }
+  if (request_it == requests_.end())
+    return;
 
-    // Loop through all device types for this request.
-    for (StreamDeviceInfoArray::const_iterator device_it = devices.begin();
-         device_it != devices.end(); ++device_it) {
-      StreamDeviceInfo device_info = *device_it;
-
-      // Set in_use to false to be able to track if this device has been
-      // opened. in_use might be true if the device type can be used in more
-      // than one session.
-      DCHECK_EQ(request_it->second.state[device_it->stream_type],
-                DeviceRequest::STATE_PENDING_APPROVAL);
-      device_info.in_use = false;
-      device_info.session_id =
-          GetDeviceManager(device_info.stream_type)->Open(device_info);
-      request_it->second.state[device_it->stream_type] =
-          DeviceRequest::STATE_OPENING;
-      if (device_info.stream_type ==
-          content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE) {
-        request_it->second.audio_devices.push_back(device_info);
-      } else if (device_info.stream_type ==
-                 content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE) {
-        request_it->second.video_devices.push_back(device_info);
-      } else {
-        NOTREACHED();
-      }
-    }
-    // Check if we received all stream types requested.
-    MediaStreamType stream_type =
-        content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE;
-    if (Requested(request_it->second.options, stream_type) &&
-        request_it->second.audio_devices.size() == 0) {
-      request_it->second.state[stream_type] = DeviceRequest::STATE_ERROR;
-    }
-    stream_type = content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE;
-    if (Requested(request_it->second.options, stream_type) &&
-        request_it->second.video_devices.size() == 0) {
-      request_it->second.state[stream_type] = DeviceRequest::STATE_ERROR;
-    }
+  DeviceRequest& request = request_it->second;
+
+  if (devices.empty()) {
+    // No available devices or user didn't accept device usage.
+    request.requester->StreamGenerationFailed(request_it->first);
+    requests_.erase(request_it);
     return;
   }
+
+  // Process all newly-accepted devices for this request.
+  for (StreamDeviceInfoArray::const_iterator device_it = devices.begin();
+       device_it != devices.end(); ++device_it) {
+    StreamDeviceInfo device_info = *device_it;  // Make a copy.
+
+    // Set in_use to false to be able to track if this device has been
+    // opened. in_use might be true if the device type can be used in more
+    // than one session.
+    DCHECK_EQ(request.state[device_it->stream_type],
+              DeviceRequest::STATE_PENDING_APPROVAL);
+    device_info.in_use = false;
+    device_info.session_id =
+        GetDeviceManager(device_info.stream_type)->Open(device_info);
+    request.state[device_it->stream_type] = DeviceRequest::STATE_OPENING;
+    request.devices.push_back(device_info);
+  }
+
+  // Check whether we've received all stream types requested.
+  bool found_audio = false, found_video = false;
+  for (StreamDeviceInfoArray::const_iterator i = request.devices.begin();
+       i != request.devices.end(); ++i) {

[wjia(left Chromium), 2012/09/07 14:11:36]

This for loop can be merged with for loop above.

[miu, 2012/09/07 23:14:28]

Done.

+    if (i->stream_type == request.options.audio_type) {
+      found_audio = true;
+    } else if (i->stream_type == request.options.video_type) {
+      found_video = true;
+    } else {
+      NOTREACHED();
+    }
+  }
+  if (request.options.audio_type != content::MEDIA_NO_SERVICE &&
+      !found_audio) {
+    request.state[request.options.audio_type] = DeviceRequest::STATE_ERROR;
+  }
+  if (request.options.video_type != content::MEDIA_NO_SERVICE &&
+      !found_video) {
+    request.state[request.options.video_type] = DeviceRequest::STATE_ERROR;
+  }
 }
 
 void MediaStreamManager::SettingsError(const std::string& label) {
@@ -689,9 +750,21 @@ void MediaStreamManager::SettingsError(const std::string& label) {
   }
 }
 
+void MediaStreamManager::SetAudioManager(media::AudioManager* audio_manager) {
+  LOG_IF(FATAL, (audio_manager_ != NULL) && (audio_manager_ != audio_manager))
+      << "Cannot override AudioManager after it has been set.";
+  audio_manager_ = audio_manager;
+}
+
 void MediaStreamManager::UseFakeDevice() {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  video_capture_manager()->UseFakeDevice();
+  for (int i = content::MEDIA_NO_SERVICE + 1; i < content::NUM_MEDIA_TYPES;
+       ++i) {
+    const MediaStreamType stream_type = static_cast<MediaStreamType>(i);
+    if (content::IsVideoMediaType(stream_type)) {
+      GetVideoCaptureManager(stream_type)->UseFakeDevice();
+    }
+  }
   device_settings_->UseFakeUI();
 }
 
@@ -701,13 +774,20 @@ void MediaStreamManager::WillDestroyCurrentMessageLoop() {
   if (device_thread_.get()) {
     StopMonitoring();
 
-    video_capture_manager_->Unregister();
-    audio_input_device_manager_->Unregister();
+    for (int i = content::MEDIA_NO_SERVICE + 1; i < content::NUM_MEDIA_TYPES;
+         ++i) {
+      if (device_manager_[i]) {
+        device_manager_[i]->Unregister();
+      }
+    }
+
     device_thread_.reset();
   }
 
-  audio_input_device_manager_ = NULL;
-  video_capture_manager_ = NULL;
+  for (int i = content::MEDIA_NO_SERVICE + 1; i < content::NUM_MEDIA_TYPES;
+       ++i) {
+    device_manager_[i] = NULL;
+  }
   io_loop_ = NULL;
   device_settings_.reset();
 }
@@ -737,84 +817,85 @@ void MediaStreamManager::NotifyObserverDevicesClosed(DeviceRequest* request) {
 
 void MediaStreamManager::DevicesFromRequest(
     DeviceRequest* request, content::MediaStreamDevices* devices) {
-  StreamDeviceInfoArray::const_iterator it = request->audio_devices.begin();
-  for (; it != request->audio_devices.end(); ++it) {
-    devices->push_back(
-        content::MediaStreamDevice(
-            content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE,
-            it->device_id,
-            it->name));
-  }
-  for (it = request->video_devices.begin(); it != request->video_devices.end();
-       ++it) {
-    devices->push_back(
-        content::MediaStreamDevice(
-            content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE,
-            it->device_id,
-            it->name));
+  for (StreamDeviceInfoArray::const_iterator it = request->devices.begin();
+       it != request->devices.end(); ++it) {
+    devices->push_back(content::MediaStreamDevice(
+        it->stream_type, it->device_id, it->name));
   }
 }
 
 bool MediaStreamManager::RequestDone(const DeviceRequest& request) const {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
-  // Check if all devices are opened.
-  MediaStreamType stream_type = content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE;
-  if (Requested(request.options, stream_type)) {
-    if (request.state[stream_type] != DeviceRequest::STATE_DONE &&
-        request.state[stream_type] != DeviceRequest::STATE_ERROR) {
-      return false;
-    }
 
-    for (StreamDeviceInfoArray::const_iterator it =
-         request.audio_devices.begin(); it != request.audio_devices.end();
-         ++it) {
-      if (it->in_use == false) {
-        return false;
-      }
-    }
+  const bool requested_audio =
+      content::IsAudioMediaType(request.options.audio_type);
+  const bool requested_video =
+      content::IsVideoMediaType(request.options.video_type);
+
+  const bool audio_done =
+      !requested_audio ||
+      request.state[request.options.audio_type] == DeviceRequest::STATE_DONE ||
+      request.state[request.options.audio_type] == DeviceRequest::STATE_ERROR;
+  if (!audio_done) {
+    return false;
   }
 
-  stream_type = content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE;
-  if (Requested(request.options, stream_type)) {
-    if (request.state[stream_type] != DeviceRequest::STATE_DONE &&
-        request.state[stream_type] != DeviceRequest::STATE_ERROR) {
-      return false;
-    }
+  const bool video_done =
+      !requested_video ||
+      request.state[request.options.video_type] == DeviceRequest::STATE_DONE ||
+      request.state[request.options.video_type] == DeviceRequest::STATE_ERROR;
+  if (!video_done) {
+    return false;
+  }
 
-    for (StreamDeviceInfoArray::const_iterator it =
-         request.video_devices.begin(); it != request.video_devices.end();
-         ++it) {
-      if (it->in_use == false) {
-        return false;
-      }
+  for (StreamDeviceInfoArray::const_iterator it = request.devices.begin();
+       it != request.devices.end(); ++it) {
+    if ((!requested_audio && content::IsAudioMediaType(it->stream_type)) ||
+        (!requested_video && content::IsVideoMediaType(it->stream_type))) {

[wjia(left Chromium), 2012/09/07 14:11:36]

This won't happen since the "request" only accepts types of devices it has
requested in DevicesEnumerated().

[miu, 2012/09/07 23:14:28]

Done.

+      continue;
+    }
+    if (it->in_use == false) {
+      return false;
     }
   }
 
   return true;
 }
 
-// Called to get media capture device manager of specified type.
 MediaStreamProvider* MediaStreamManager::GetDeviceManager(
     MediaStreamType stream_type) {
-  if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE) {
-    return video_capture_manager();
-  } else if (stream_type == content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE) {
-    return audio_input_device_manager();
-  }
-  NOTREACHED();
-  return NULL;
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+  EnsureDeviceManagerStarted(stream_type);
+  return device_manager_[stream_type];
+}
+
+VideoCaptureManager* MediaStreamManager::GetVideoCaptureManager(
+    MediaStreamType stream_type) {
+  DCHECK(content::IsVideoMediaType(stream_type));
+  return reinterpret_cast<VideoCaptureManager*>(GetDeviceManager(stream_type));
+}
+
+AudioInputDeviceManager* MediaStreamManager::GetAudioInputDeviceManager(
+    MediaStreamType stream_type) {
+  DCHECK(content::IsAudioMediaType(stream_type));
+  return reinterpret_cast<AudioInputDeviceManager*>(
+      GetDeviceManager(stream_type));
 }
 
 void MediaStreamManager::OnDevicesChanged(
     base::SystemMonitor::DeviceType device_type) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::IO));
+
+  // NOTE: This method is only called in response to physical audio/video device
+  // changes (from the operating system).
+
   MediaStreamType stream_type;
   EnumerationCache* cache;
   if (device_type == base::SystemMonitor::DEVTYPE_AUDIO_CAPTURE) {
-    stream_type = content::MEDIA_STREAM_DEVICE_TYPE_AUDIO_CAPTURE;
+    stream_type = content::MEDIA_AUDIO_DEVICE_CAPTURE;
     cache = &audio_enumeration_cache_;
   } else if (device_type == base::SystemMonitor::DEVTYPE_VIDEO_CAPTURE) {
-    stream_type = content::MEDIA_STREAM_DEVICE_TYPE_VIDEO_CAPTURE;
+    stream_type = content::MEDIA_VIDEO_DEVICE_CAPTURE;
     cache = &video_enumeration_cache_;
   } else {
     return;  // Uninteresting device change.