Remove base::SupportsWeakPtr from {Audio,Video}Sender

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 8447223d1e93ee14aab7c426e3dbe1deec980787..05b0748c36e0fc833493b15c6f41bf36d9edf58f 100644
--- a/media/cast/sender/video_sender.cc
+++ b/media/cast/sender/video_sender.cc
@@ -110,8 +110,7 @@ VideoSender::VideoSender(
       playout_delay_change_cb_(playout_delay_change_cb),
       low_latency_mode_(false),
       last_reported_encoder_utilization_(-1.0),
-      last_reported_lossy_utilization_(-1.0),
-      weak_factory_(this) {
+      last_reported_lossy_utilization_(-1.0) {
   video_encoder_ = VideoEncoder::Create(
       cast_environment_,
       video_config,
@@ -257,8 +256,8 @@ void VideoSender::InsertRawVideoFrame(
           last_reported_lossy_utilization_, video_frame);
   if (video_encoder_->EncodeVideoFrame(
           frame_to_encode, reference_time,
-          base::Bind(&VideoSender::OnEncodedVideoFrame,
-                     weak_factory_.GetWeakPtr(), frame_to_encode, bitrate))) {
+          base::Bind(&VideoSender::OnEncodedVideoFrame, AsWeakPtr(),
+                     frame_to_encode, bitrate))) {
     TRACE_EVENT_ASYNC_BEGIN1("cast.stream", "Video Encode",
                              frame_to_encode.get(), "rtp_timestamp",
                              rtp_timestamp.lower_32_bits());