Shows dialog when lib-jitsi-meet report microphone issues

conference.js

 
         return promise.then(function () {
             if (stream) {
+                stream.on(TrackEvents.TRACK_AUDIO_NOT_WORKING,
+                    APP.UI.showAudioNotWorkingDialog);
                 return room.addTrack(stream);
             }
         }).then(() => {
         });
 
         room.on(ConferenceEvents.LOCK_STATE_CHANGED, (state, error) => {
-            console.log("Received channel password lock change: ", state, error);
+            console.log("Received channel password lock change: ", state,
+                error);
             APP.UI.markRoomLocked(state);
         });
 

lang/main.json

         "micPermissionDeniedError": "You have not granted permission to use your microphone. You can still join the conference but others won't hear you. Use the camera button in the address bar to fix this.",
         "micNotFoundError": "Microphone was not found.",
         "micConstraintFailedError": "Yor microphone does not satisfy some of required constraints.",
+        "micNotSendingData": "Your microphone is not sending data. Please select another device from the settings menu or try to restart your browser / device.",
         "goToStore": "Go to the webstore",
         "externalInstallationTitle": "Extension required",
         "externalInstallationMsg": "You need to install our desktop sharing extension."

modules/UI/UI.js

     }
 };
 
+/**
+ * Shows error dialog that informs the user that no data is received from the
+ * microphone.
+ */
+UI.showAudioNotWorkingDialog = function () {
+    messageHandler.openMessageDialog(
+        "dialog.error",
+        "dialog.micNotSendingData",
+        null,
+        null);
+};
+
 UI.updateDevicesAvailability = function (id, devices) {
     VideoLayout.setDeviceAvailabilityIcons(id, devices);
 };