fix: honor updates of the local user role before conference join

When the prosody setting has muc_allowners, everyone joins as a
moderator. In this case, the local user will not be set as a
moderator in the redux store as the USER_ROLE_CHANGE event will
trigger with the local user id before the redux store has set
the actual local user id--something that happens on
CONFERENCE_JOINED. The fix is to explicitly signal the local user
role has changed to the redux store, which follows the
implementation of pre-existing web logic.

conference.js

@@ -37,6 +37,7 @@ import {
     isFatalJitsiConnectionError
 } from './react/features/base/lib-jitsi-meet';
 import {
+    localParticipantRoleChanged,
     participantJoined,
     participantLeft,
     participantRoleChanged,
@@ -1262,14 +1263,18 @@ export default {
 
 
         room.on(ConferenceEvents.USER_ROLE_CHANGED, (id, role) => {
-            APP.store.dispatch(participantRoleChanged(id, role));
             if (this.isLocalId(id)) {
                 logger.info(`My role changed, new role: ${role}`);
+
+                APP.store.dispatch(localParticipantRoleChanged(role));
+
                 if (this.isModerator !== room.isModerator()) {
                     this.isModerator = room.isModerator();
                     APP.UI.updateLocalRole(room.isModerator());
                 }
             } else {
+                APP.store.dispatch(participantRoleChanged(id, role));
+
                 let user = room.getParticipantById(id);
                 if (user) {
                     APP.UI.updateUserRole(user);

react/features/base/participants/actions.js

@@ -29,15 +29,12 @@ export function dominantSpeakerChanged(id) {
 }
 
 /**
- * Action to signal that ID of local participant has changed. This happens when
+ * Action to signal that the ID of local participant has changed. It happens
- * local participant joins a new conference or quits one.
+ * when the local participant joins a new conference or leaves an existing
+ * conference.
  *
  * @param {string} id - New ID for local participant.
- * @returns {{
+ * @returns {Function}
- *     type: PARTICIPANT_ID_CHANGED,
- *     newValue: string,
- *     oldValue: string
- * }}
  */
 export function localParticipantIdChanged(id) {
     return (dispatch, getState) => {
@@ -69,6 +66,24 @@ export function localParticipantJoined(participant = {}) {
     });
 }
 
+/**
+ * Action to signal the role of the local participant has changed. It can happen
+ * when the participant has joined a conference, even before a non-default local
+ * id has been set, or after a moderator leaves.
+ *
+ * @param {string} role - The new role of the local participant.
+ * @returns {Function}
+ */
+export function localParticipantRoleChanged(role) {
+    return (dispatch, getState) => {
+        const participant = getLocalParticipant(getState);
+
+        if (participant) {
+            return dispatch(participantRoleChanged(participant.id, role));
+        }
+    };
+}
+
 /**
  * Action to update a participant's connection status.
  *