Prevent double mute status changed events (#2502)

Audio & video mute status were set in separate calls but share a
mute status changed event, so you'd always get two mute status
changed events emitted. We could suppress events where the mute
status didn't change, but this would still get two events saying
the same thing when they both changed. Instead, merge setAudioMuted
& setVideoMuted into a single call that sets either or both.

Port of #2502 from
group call branch

src/webrtc/call.ts

@@ -1142,7 +1142,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
             await this.upgradeCall(false, true);
             return this.isLocalVideoMuted();
         }
-        this.localUsermediaFeed?.setVideoMuted(muted);
+        this.localUsermediaFeed?.setAudioVideoMuted(null, muted);
         this.updateMuteStatus();
         return this.isLocalVideoMuted();
     }
@@ -1174,7 +1174,7 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
             await this.upgradeCall(true, false);
             return this.isMicrophoneMuted();
         }
-        this.localUsermediaFeed?.setAudioMuted(muted);
+        this.localUsermediaFeed?.setAudioVideoMuted(muted, null);
         this.updateMuteStatus();
         return this.isMicrophoneMuted();
     }
@@ -1585,8 +1585,9 @@ export class MatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap
         this.remoteSDPStreamMetadata = utils.recursivelyAssign(this.remoteSDPStreamMetadata || {}, metadata, true);
         for (const feed of this.getRemoteFeeds()) {
             const streamId = feed.stream.id;
-            feed.setAudioMuted(this.remoteSDPStreamMetadata[streamId]?.audio_muted);
-            feed.setVideoMuted(this.remoteSDPStreamMetadata[streamId]?.video_muted);
+            const metadata = this.remoteSDPStreamMetadata[streamId];
+
+            feed.setAudioVideoMuted(metadata?.audio_muted, metadata?.video_muted);
             feed.purpose = this.remoteSDPStreamMetadata[streamId]?.purpose;
         }
     }

src/webrtc/callFeed.ts

@@ -184,21 +184,18 @@ export class CallFeed extends TypedEventEmitter<CallFeedEvent, EventHandlerMap>
     }
 
     /**
-     * Set feed's internal audio mute state
-     * @param muted is the feed's audio muted?
-     */
-    public setAudioMuted(muted: boolean): void {
-        this.audioMuted = muted;
-        this.speakingVolumeSamples.fill(-Infinity);
-        this.emit(CallFeedEvent.MuteStateChanged, this.audioMuted, this.videoMuted);
-    }
-
-    /**
-     * Set feed's internal video mute state
+     * Set one or both of feed's internal audio and video video mute state
+     * Either value may be null to leave it as-is
      * @param muted is the feed's video muted?
      */
-    public setVideoMuted(muted: boolean): void {
-        this.videoMuted = muted;
+    public setAudioVideoMuted(audioMuted: boolean, videoMuted: boolean): void {
+        if (audioMuted !== null) {
+            if (this.audioMuted !== audioMuted) {
+                this.speakingVolumeSamples.fill(-Infinity);
+            }
+            this.audioMuted = audioMuted;
+        }
+        if (videoMuted !== null) this.videoMuted = videoMuted;
         this.emit(CallFeedEvent.MuteStateChanged, this.audioMuted, this.videoMuted);
     }