Pass camera facing to WebKit

content/browser/renderer_host/media/media_stream_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/media_stream_manager.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <algorithm>
@@ skipping 31 matching lines @@
 #include "content/public/browser/web_contents_media_capture_id.h"
 #include "content/public/common/content_client.h"
 #include "content/public/common/content_switches.h"
 #include "content/public/common/media_stream_request.h"
 #include "crypto/hmac.h"
 #include "media/audio/audio_device_description.h"
 #include "media/audio/audio_manager.h"
 #include "media/base/audio_parameters.h"
 #include "media/base/channel_layout.h"
 #include "media/base/media_switches.h"
+#include "media/capture/video/linux/camera_facing_chromeos.h"

[jochen (gone - plz use gerrit), 2017/01/05 12:17:59]

we shouldn't unconditionally include platform specific headers

[shenghao, 2017/01/06 09:43:01]

Done.

 #include "media/capture/video/video_capture_device_factory.h"
 #include "url/gurl.h"
 #include "url/origin.h"
 
 #if defined(OS_WIN)
 #include "base/win/scoped_com_initializer.h"
 #endif
 
 #if defined(OS_CHROMEOS)
 #include "chromeos/audio/cras_audio_handler.h"
 #endif
 
 namespace content {
 
 base::LazyInstance<base::ThreadLocalPointer<MediaStreamManager>>::Leaky
     g_media_stream_manager_tls_ptr = LAZY_INSTANCE_INITIALIZER;
 
 namespace {
+
+base::LazyInstance<media::CameraFacingChromeOS>::Leaky g_camera_facing_ =

[jochen (gone - plz use gerrit), 2017/01/05 12:17:59]

why is that a singleton can't we create a new instance when we need one?

also, platform specific code should either go into platform specific files, or
needs to be #ifdef'd

[shenghao, 2017/01/06 09:43:01]

It's a lazy instance so it only be constructed when first used. We don't want to
create one instance for each use because constructing CameraFacingChromeOS
involving reading some data from file, which is slow.
done

+    LAZY_INSTANCE_INITIALIZER;
+
 // Creates a random label used to identify requests.
 std::string RandomLabel() {
   // An earlier PeerConnection spec [1] defined MediaStream::label alphabet as
   // an uuid with characters from range: U+0021, U+0023 to U+0027, U+002A to
   // U+002B, U+002D to U+002E, U+0030 to U+0039, U+0041 to U+005A, U+005E to
   // U+007E. That causes problems with searching for labels in bots, so we use a
   // safe alphanumeric subset |kAlphabet|.
   // [1] http://dev.w3.org/2011/webrtc/editor/webrtc.html
   static const char kAlphabet[] = "0123456789"
       "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
@@ skipping 120 matching lines @@
       return MEDIA_DEVICE_TYPE_AUDIO_INPUT;
     case MEDIA_DEVICE_VIDEO_CAPTURE:
       return MEDIA_DEVICE_TYPE_VIDEO_INPUT;
     default:
       NOTREACHED();
   }
 
   return NUM_MEDIA_DEVICE_TYPES;
 }
 
+VideoFacingMode GetVideoFacing(std::string device_id, std::string model_id) {
+  media::CameraFacingChromeOS::LensFacing facing =
+      g_camera_facing_.Get().GetCameraFacing(device_id, model_id);
+  switch (facing) {
+    case media::CameraFacingChromeOS::LensFacing::FRONT:
+      return VideoFacingMode::MEDIA_VIDEO_FACING_USER;
+    case media::CameraFacingChromeOS::LensFacing::BACK:
+      return VideoFacingMode::MEDIA_VIDEO_FACING_ENVIRONMENT;
+  }
+  return VideoFacingMode::MEDIA_VIDEO_FACING_NONE;
+}
+
 MediaStreamDevices ConvertToMediaStreamDevices(
     MediaStreamType stream_type,
     const MediaDeviceInfoArray& device_infos) {
   MediaStreamDevices devices;
   for (const auto& info : device_infos) {
-    devices.emplace_back(stream_type, info.device_id, info.label);
+    devices.emplace_back(stream_type, info.device_id, info.label,
+                         GetVideoFacing(info.device_id, info.model_id));
   }
 
   return devices;
 }
 
 }  // namespace
 
 
 // MediaStreamManager::DeviceRequest represents a request to either enumerate
 // available devices or open one or more devices.
@@ skipping 1517 matching lines @@
   generate_stream_test_callback_ = test_callback;
 }
 
 #if defined(OS_WIN)
 void MediaStreamManager::FlushVideoCaptureThreadForTesting() {
   video_capture_thread_.FlushForTesting();
 }
 #endif
 
 }  // namespace content