Bug 1921154 - add AV1 pref;r=pehrsons

Differential Revision: https://phabricator.services.mozilla.com/D223803

dom/media/webrtc/libwebrtcglue/VideoConduit.cpp

@@ -2080,6 +2080,14 @@ bool WebrtcVideoConduit::HasH264Hardware() {
          status == nsIGfxInfo::FEATURE_STATUS_OK;
 }
 
+bool WebrtcVideoConduit::HasAv1() {
+#if defined(MOZ_AV1)
+  return true;
+#else
+  return false;
+#endif
+}
+
 Maybe<int> WebrtcVideoConduit::ActiveSendPayloadType() const {
   MOZ_ASSERT(mCallThread->IsOnCurrentThread());
 

dom/media/webrtc/libwebrtcglue/VideoConduit.h

@@ -69,6 +69,8 @@ class WebrtcVideoConduit
  public:
   // Returns true when both encoder and decoder are HW accelerated.
   static bool HasH264Hardware();
+  // Returns true when AV1 is supported in the build.
+  static bool HasAv1();
 
   Maybe<int> ActiveSendPayloadType() const override;
   Maybe<int> ActiveRecvPayloadType() const override;

modules/libpref/init/StaticPrefList.yaml

@@ -11996,6 +11996,15 @@
 #endif
   mirror: always
 
+- name: media.webrtc.codec.video.av1.enabled
+  type: RelaxedAtomicBool
+#if defined(MOZ_AV1)
+  value: @IS_NIGHTLY_BUILD@
+#else
+  value: false
+#endif
+  mirror: always
+
 - name: media.webrtc.tls_tunnel_for_all_proxy
   type: bool
   value: true