Bug 1851693 - Vendor libwebrtc from 402f60c2ea

Upstream commit: https://webrtc.googlesource.com/src/+/402f60c2eabefbc7a120ec01659690c7fdf89769
    [Merge to 116] CHECK against overwrites in send_modules_map_

    (cherry picked from commit 9d8fb97b3ca56ec9920271d8e545ae2ac76b143c)

    No-try: true
    Bug: chromium:1477075
    Change-Id: Ia05a868bfab9e99ef66704e8d6bce516a7a43b0a
    Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/318440
    Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
    Commit-Queue: Harald Alvestrand <hta@webrtc.org>
    Cr-Original-Commit-Position: refs/heads/main@{#40673}
    Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/319320
    Reviewed-by: Philipp Hancke <phancke@microsoft.com>
    Reviewed-by: Taylor Brandstetter <deadbeef@webrtc.org>
    Cr-Commit-Position: refs/branch-heads/5845@{#7}
    Cr-Branched-From: f80cf814353d11a9f22bef5ce5e8868f2c72f0d0-refs/heads/main@{#40319}

third_party/libwebrtc/README.moz-ff-commit

@@ -24657,3 +24657,6 @@ aa6c910f47
 # MOZ_LIBWEBRTC_SRC=/Users/mfroman/no_tm_backup/elm/.moz-fast-forward/moz-libwebrtc MOZ_LIBWEBRTC_BRANCH=mozpatches bash dom/media/webrtc/third_party_build/fast-forward-libwebrtc.sh
 # base of lastest vendoring
 44bc8e96ed
+# MOZ_LIBWEBRTC_SRC=/Users/mfroman/no_tm_backup/elm/.moz-fast-forward/moz-libwebrtc MOZ_LIBWEBRTC_BRANCH=mozpatches bash dom/media/webrtc/third_party_build/fast-forward-libwebrtc.sh
+# base of lastest vendoring
+402f60c2ea

third_party/libwebrtc/README.mozilla

@@ -16460,3 +16460,5 @@ libwebrtc updated from /Users/mfroman/no_tm_backup/elm/.moz-fast-forward/moz-lib
 libwebrtc updated from /Users/mfroman/no_tm_backup/elm/.moz-fast-forward/moz-libwebrtc commit mozpatches on 2023-09-27T04:08:52.973541.
 # ./mach python dom/media/webrtc/third_party_build/vendor-libwebrtc.py --from-local /Users/mfroman/no_tm_backup/elm/.moz-fast-forward/moz-libwebrtc --commit mozpatches libwebrtc
 libwebrtc updated from /Users/mfroman/no_tm_backup/elm/.moz-fast-forward/moz-libwebrtc commit mozpatches on 2023-09-27T04:10:08.028101.
+# ./mach python dom/media/webrtc/third_party_build/vendor-libwebrtc.py --from-local /Users/mfroman/no_tm_backup/elm/.moz-fast-forward/moz-libwebrtc --commit mozpatches libwebrtc
+libwebrtc updated from /Users/mfroman/no_tm_backup/elm/.moz-fast-forward/moz-libwebrtc commit mozpatches on 2023-09-27T04:11:23.619074.

third_party/libwebrtc/modules/pacing/packet_router.cc

@@ -68,7 +68,7 @@ void PacketRouter::AddSendRtpModule(RtpRtcpInterface* rtp_module,
 void PacketRouter::AddSendRtpModuleToMap(RtpRtcpInterface* rtp_module,
                                          uint32_t ssrc) {
   RTC_DCHECK_RUN_ON(&thread_checker_);
-  RTC_DCHECK(send_modules_map_.find(ssrc) == send_modules_map_.end());
+  RTC_CHECK(send_modules_map_.find(ssrc) == send_modules_map_.end());
 
   // Signal to module that the pacer thread is attached and can send packets.
   rtp_module->OnPacketSendingThreadSwitched();