Add Deinit() to the destructors of Voice/Video/RtpDataChannel.

This is a follow up CL of
https://webrtc-review.googlesource.com/c/src/+/59586.

The Deinit() method is not added because of some merging issue.

Bug: none
Change-Id: If23b0619a027379b920d4113ec507bff087d44fd
Reviewed-on: https://webrtc-review.googlesource.com/65787
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Commit-Queue: Zhi Huang <zhihuang@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22694}
diff --git a/pc/channel.cc b/pc/channel.cc
index 6da6470..2aab718 100644
--- a/pc/channel.cc
+++ b/pc/channel.cc
@@ -704,6 +704,7 @@
   TRACE_EVENT0("webrtc", "VoiceChannel::~VoiceChannel");
   // this can't be done in the base class, since it calls a virtual
   DisableMedia_w();
+  Deinit();
 }
 
 void BaseChannel::UpdateMediaSendRecvState() {
@@ -835,6 +836,7 @@
   TRACE_EVENT0("webrtc", "VideoChannel::~VideoChannel");
   // this can't be done in the base class, since it calls a virtual
   DisableMedia_w();
+  Deinit();
 }
 
 void VideoChannel::UpdateMediaSendRecvState_w() {
@@ -965,6 +967,7 @@
   TRACE_EVENT0("webrtc", "RtpDataChannel::~RtpDataChannel");
   // this can't be done in the base class, since it calls a virtual
   DisableMedia_w();
+  Deinit();
 }
 
 void RtpDataChannel::Init_w(webrtc::RtpTransportInternal* rtp_transport) {