Close all writers before JingleSession is destroyed.

remoting/protocol/rtp_video_writer.cc

Index: remoting/protocol/rtp_video_writer.cc
diff --git a/remoting/protocol/rtp_video_writer.cc b/remoting/protocol/rtp_video_writer.cc
index da16444a7acec26b8435ac016ed975820b01bcfc..d5d4b752236430ea21435c7536f6918910c4b501 100644
--- a/remoting/protocol/rtp_video_writer.cc
+++ b/remoting/protocol/rtp_video_writer.cc
@@ -20,12 +20,18 @@ const int kMtu = 1200;
 
 RtpVideoWriter::RtpVideoWriter() { }
 
-RtpVideoWriter::~RtpVideoWriter() { }
+RtpVideoWriter::~RtpVideoWriter() {
+  Close();
+}
 
 void RtpVideoWriter::Init(protocol::Session* session) {
   rtp_writer_.Init(session->video_rtp_channel());
 }
 
+void RtpVideoWriter::Close() {
+  rtp_writer_.Close();
+}
+
 void RtpVideoWriter::ProcessVideoPacket(const VideoPacket* packet, Task* done) {
   CHECK(packet->format().encoding() == VideoPacketFormat::ENCODING_VP8)
       << "Only VP8 is supported in RTP.";