fix(always-on-top) Fix audio mute button disabled status

modules/API/API.js

 import { playSharedVideo, stopSharedVideo } from '../../react/features/shared-video/actions.any';
 import { extractYoutubeIdOrURL } from '../../react/features/shared-video/functions';
 import { toggleRequestingSubtitles, setRequestingSubtitles } from '../../react/features/subtitles/actions';
+import { isAudioMuteButtonDisabled } from '../../react/features/toolbox/functions';
 import { toggleTileView, setTileView } from '../../react/features/video-layout';
 import { muteAllParticipants } from '../../react/features/video-menu/actions';
 import { setVideoQuality } from '../../react/features/video-quality';
         case 'is-audio-muted':
             callback(APP.conference.isLocalAudioMuted());
             break;
+        case 'is-audio-disabled':
+            callback(isAudioMuteButtonDisabled(APP.store.getState()));
+            break;
         case 'is-moderation-on': {
             const { mediaType } = request;
             const type = mediaType || MEDIA_TYPE.AUDIO;

modules/API/external/external_api.js

         });
     }
 
+    /**
+     * Returns the audio disabled status.
+     *
+     * @returns {Promise} - Resolves with the audio disabled status and rejects on
+     * failure.
+     */
+    isAudioDisabled() {
+        return this._transport.sendRequest({
+            name: 'is-audio-disabled'
+        });
+    }
+
     /**
      * Returns the moderation on status on the given mediaType.
      *

react/features/always-on-top/AudioMuteButton.js

         Promise.all([
             api.isAudioAvailable(),
             api.isAudioMuted(),
-            api.isStartSilent()
+            api.isAudioDisabled?.() || Promise.resolve(false)
         ])
-            .then(([ audioAvailable, audioMuted, startSilent ]) =>
+            .then(([ audioAvailable, audioMuted, audioDisabled ]) =>
                 this.setState({
-                    audioAvailable: audioAvailable && !startSilent,
+                    audioAvailable: audioAvailable && !audioDisabled,
                     audioMuted
                 }))
             .catch(console.error);

react/features/toolbox/functions.any.js

     const { available, muted, unmuteBlocked } = state['features/base/media'].audio;
     const { startSilent } = state['features/base/config'];
 
-    return !available || startSilent || (muted && unmuteBlocked);
+    return Boolean(!available || startSilent || (muted && unmuteBlocked));
 }