Pass camera facing info to audio client

content/browser/renderer_host/media/video_capture_manager.cc

Index: content/browser/renderer_host/media/video_capture_manager.cc
diff --git a/content/browser/renderer_host/media/video_capture_manager.cc b/content/browser/renderer_host/media/video_capture_manager.cc
index 9f7b8f170846fb1e73c8fe7b462852f8e05a9ab5..748c9c9cfe8486fa7b5b310b34e59d6344cfebda 100644
--- a/content/browser/renderer_host/media/video_capture_manager.cc
+++ b/content/browser/renderer_host/media/video_capture_manager.cc
@@ -34,6 +34,7 @@
 #include "content/public/common/media_stream_request.h"
 #include "media/base/bind_to_current_loop.h"
 #include "media/base/media_switches.h"
+#include "media/base/video_facing.h"
 #include "media/capture/video/video_capture_buffer_pool_impl.h"
 #include "media/capture/video/video_capture_buffer_tracker_factory_impl.h"
 #include "media/capture/video/video_capture_device.h"
@@ -337,6 +338,16 @@ VideoCaptureManager::~VideoCaptureManager() {
   DCHECK(device_start_queue_.empty());
 }
 
+void VideoCaptureManager::AddVideoCaptureObserver(
+    media::VideoCaptureObserver* observer) {
+  if (observer != nullptr)

[jennyz, 2017/02/09 19:42:55]

client code is not supposed to call this function passing a nullptr, what about
using a DCHECK to guard?

[shenghao, 2017/02/09 22:32:51]

Done.

+    capture_observers_.push_back(observer);
+}
+
+void VideoCaptureManager::RemoveAllVideoCaptureObservers() {
+  capture_observers_.clear();
+}
+
 void VideoCaptureManager::Register(
     MediaStreamProviderListener* listener,
     const scoped_refptr<base::SingleThreadTaskRunner>& device_task_runner) {
@@ -467,6 +478,12 @@ void VideoCaptureManager::DoStopDevice(DeviceEntry* entry) {
     }
   }
 
+  const DeviceInfo* device_info = GetDeviceInfoById(entry->id);
+  if (device_info != nullptr) {
+    for (auto& observer : capture_observers_)
+      observer->OnVideoCaptureStopped(device_info->descriptor.facing);
+  }
+
   DVLOG(3) << "DoStopDevice. Send stop request for device = " << entry->id
            << " serial_id = " << entry->serial_id << ".";
   entry->video_capture_controller.OnLog(
@@ -523,6 +540,9 @@ void VideoCaptureManager::HandleQueuedStartRequest() {
                                found->descriptor.GetNameAndModel().c_str(),
                                found->descriptor.GetCaptureApiTypeString()));
 
+        for (auto& observer : capture_observers_)
+          observer->OnVideoCaptureStarted(found->descriptor.facing);
+
         start_capture_function =
             base::Bind(&VideoCaptureManager::DoStartDeviceCaptureOnDeviceThread,
                        this, found->descriptor, request->params(),