getUserMeida: report device starting states

media/capture/video/file_video_capture_device.cc

Index: media/capture/video/file_video_capture_device.cc
diff --git a/media/capture/video/file_video_capture_device.cc b/media/capture/video/file_video_capture_device.cc
index bdac8fbfe0bae6edb2cb5a07dced625f77c99bfc..14d835c25b9ba5f32ece71a406312c72040134c5 100644
--- a/media/capture/video/file_video_capture_device.cc
+++ b/media/capture/video/file_video_capture_device.cc
@@ -299,7 +299,7 @@ std::unique_ptr<VideoFileParser> FileVideoCaptureDevice::GetVideoFileParser(
 }
 
 FileVideoCaptureDevice::FileVideoCaptureDevice(const base::FilePath& file_path)
-    : capture_thread_("CaptureThread"), file_path_(file_path) {}
+    : capture_thread_("CaptureThread"), file_path_(file_path), capture_(0) {}
 
 FileVideoCaptureDevice::~FileVideoCaptureDevice() {
   DCHECK(thread_checker_.CalledOnValidThread());
@@ -347,6 +347,8 @@ void FileVideoCaptureDevice::OnAllocateAndStart(
 
   DVLOG(1) << "Opened video file " << capture_format_.frame_size.ToString()
            << ", fps: " << capture_format_.frame_rate;
+  client_->OnStarted();
+  capture_ = true;
 
   capture_thread_.task_runner()->PostTask(
       FROM_HERE, base::Bind(&FileVideoCaptureDevice::OnCaptureTask,
@@ -355,6 +357,7 @@ void FileVideoCaptureDevice::OnAllocateAndStart(
 
 void FileVideoCaptureDevice::OnStopAndDeAllocate() {
   DCHECK(capture_thread_.task_runner()->BelongsToCurrentThread());
+  capture_ = false;
   file_parser_.reset();
   client_.reset();
   next_frame_time_ = base::TimeTicks();
@@ -362,7 +365,7 @@ void FileVideoCaptureDevice::OnStopAndDeAllocate() {
 
 void FileVideoCaptureDevice::OnCaptureTask() {
   DCHECK(capture_thread_.task_runner()->BelongsToCurrentThread());
-  if (!client_)
+  if (!client_ || !capture_)
     return;
 
   // Give the captured frame to the client.