Bug 1766646 - Vendor libwebrtc from 2c761b2212

Upstream commit: https://webrtc.googlesource.com/src/+/2c761b22126e261d8696d4325c89a695189246f1
    Eliminate channel.h from peer_connection.cc

    This limits the exposure of the implementation of ChannelInterface.

    Bug: webrtc:13931
    Change-Id: Ifc0fa496c210413d81ad71f44fa4040b881d092c
    Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/260561
    Reviewed-by: Henrik Boström <hbos@webrtc.org>
    Commit-Queue: Harald Alvestrand <hta@webrtc.org>
    Cr-Commit-Position: refs/heads/main@{#36725}

third_party/libwebrtc/README.moz-ff-commit

@@ -13713,3 +13713,6 @@ a5fecb3917
 # MOZ_LIBWEBRTC_SRC=/home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src MOZ_LIBWEBRTC_COMMIT=mjfdev bash dom/media/webrtc/third_party_build/fast-forward-libwebrtc.sh
 # base of lastest vendoring
 5e354d9969
+# MOZ_LIBWEBRTC_SRC=/home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src MOZ_LIBWEBRTC_COMMIT=mjfdev bash dom/media/webrtc/third_party_build/fast-forward-libwebrtc.sh
+# base of lastest vendoring
+2c761b2212

third_party/libwebrtc/README.mozilla

@@ -9154,3 +9154,5 @@ libwebrtc updated from /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwe
 libwebrtc updated from /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src commit mjfdev on 2022-07-14T16:26:44.823038.
 # python3 vendor-libwebrtc.py --from-local /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src --commit mjfdev libwebrtc
 libwebrtc updated from /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src commit mjfdev on 2022-07-14T16:27:25.461895.
+# python3 vendor-libwebrtc.py --from-local /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src --commit mjfdev libwebrtc
+libwebrtc updated from /home/mfroman/git-checkouts/trial-webrtc-builds/moz-libwebrtc-checkout/src commit mjfdev on 2022-07-14T16:28:04.770933.

third_party/libwebrtc/pc/peer_connection.cc

@@ -42,7 +42,6 @@
 #include "p2p/base/p2p_constants.h"
 #include "p2p/base/p2p_transport_channel.h"
 #include "p2p/base/transport_info.h"
-#include "pc/channel.h"
 #include "pc/ice_server_parsing.h"
 #include "pc/rtp_receiver.h"
 #include "pc/rtp_receiver_proxy.h"
@@ -1559,10 +1558,10 @@ RTCError PeerConnection::SetConfiguration(
       if (transceiver->media_type() != cricket::MEDIA_TYPE_VIDEO)
         continue;
 
-      auto* video_channel = static_cast<cricket::VideoChannel*>(
+      auto* video_channel = transceiver->internal()->channel();
-          transceiver->internal()->channel());
       if (video_channel)
-        channels.push_back(video_channel->media_channel());
+        channels.push_back(static_cast<cricket::VideoMediaChannel*>(
+            video_channel->media_channel()));
     }
 
     worker_thread()->Invoke<void>(