Cast: Flow hw encoder initialization error to extensions API

media/cast/sender/video_sender.cc

Index: media/cast/sender/video_sender.cc
diff --git a/media/cast/sender/video_sender.cc b/media/cast/sender/video_sender.cc
index 1552749015d14c0bf45779520f930fcfc8ddde08..57d09843e890c76701803a3ccb79c6dc6c5dc211 100644
--- a/media/cast/sender/video_sender.cc
+++ b/media/cast/sender/video_sender.cc
@@ -38,6 +38,7 @@ size_t GetFixedBitrate(const VideoSenderConfig& video_config) {
 VideoSender::VideoSender(
     scoped_refptr<CastEnvironment> cast_environment,
     const VideoSenderConfig& video_config,
+    const CastInitializationCallback& initialization_cb,
     const CreateVideoEncodeAcceleratorCallback& create_vea_cb,
     const CreateVideoEncodeMemoryCallback& create_video_encode_mem_cb,
     CastTransportSender* const transport_sender)
@@ -64,15 +65,26 @@ VideoSender::VideoSender(
   DCHECK_GT(max_unacked_frames_, 0);
 
   if (video_config.use_external_encoder) {
-    video_encoder_.reset(new ExternalVideoEncoder(cast_environment,
-                                                  video_config,
-                                                  create_vea_cb,
-                                                  create_video_encode_mem_cb));
+    video_encoder_.reset(new ExternalVideoEncoder(
+        cast_environment,
+        video_config,
+        base::Bind(&VideoSender::OnEncoderInitialized,
+                   weak_factory_.GetWeakPtr(), initialization_cb),
+        create_vea_cb,
+        create_video_encode_mem_cb));
   } else {
+    // Software encoder is initialized immediately.
     video_encoder_.reset(new VideoEncoderImpl(
         cast_environment, video_config, max_unacked_frames_));
+    cast_initialization_status_ = STATUS_VIDEO_INITIALIZED;
+  }
+
+  if (cast_initialization_status_ == STATUS_VIDEO_INITIALIZED) {
+    cast_environment->PostTask(
+        CastEnvironment::MAIN,
+        FROM_HERE,
+        base::Bind(initialization_cb, cast_initialization_status_));
   }
-  cast_initialization_status_ = STATUS_VIDEO_INITIALIZED;
 
   media::cast::CastTransportRtpConfig transport_config;
   transport_config.ssrc = video_config.ssrc;
@@ -214,6 +226,13 @@ void VideoSender::SendEncodedVideoFrame(
   transport_sender_->InsertFrame(ssrc_, *encoded_frame);
 }
 
+void VideoSender::OnEncoderInitialized(
+    const CastInitializationCallback& initialization_cb,
+    CastInitializationStatus status) {
+  cast_initialization_status_ = status;
+  initialization_cb.Run(status);
+}
+
 void VideoSender::OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback) {
   DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));