Bug 1766646 - Vendor libwebrtc from 56ed4680c4

Upstream commit: https://webrtc.googlesource.com/src/+/56ed4680c457935f813ae36ce24324df7780b210
    Add GN arg to force RTC_DLOG to be ON.

    Bug: None
    Change-Id: I7f5e80c015157718bb3f1d192b0c14f09f9bf3bf
    Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/234840
    Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
    Reviewed-by: Markus Handell <handellm@webrtc.org>
    Cr-Commit-Position: refs/heads/main@{#35184}

third_party/libwebrtc/BUILD.gn

@@ -118,6 +118,10 @@ config("common_inherited_config") {
   cflags = []
   ldflags = []
 
+  if (rtc_dlog_always_on) {
+    defines += [ "DLOG_ALWAYS_ON" ]
+  }
+
   if (rtc_enable_symbol_export || is_component_build) {
     defines += [ "WEBRTC_ENABLE_SYMBOL_EXPORT" ]
   }

third_party/libwebrtc/README.moz-ff-commit

@@ -9090,3 +9090,6 @@ a6f195154f
 # 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
 2708a7e64c
+# 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
+56ed4680c4

third_party/libwebrtc/README.mozilla

@@ -6068,3 +6068,5 @@ 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 2022-06-10T22:55:11.205984.
 # 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 2022-06-10T22:55:51.601634.
+# 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 2022-06-10T22:56:32.678120.

third_party/libwebrtc/webrtc.gni

@@ -55,6 +55,11 @@ declare_args() {
 }
 
 declare_args() {
+  # Setting this to trye, will make RTC_DLOG() expand to log statements instead
+  # of being removed by the preprocessor.
+  # This is useful for example to be able to get RTC_DLOGs on a release build.
+  rtc_dlog_always_on = false
+
   # Setting this to true will make RTC_OBJC_EXPORT expand to code that will
   # manage symbols visibility. By default, Obj-C/Obj-C++ symbols are exported
   # if C++ symbols are but setting this arg to true while keeping