feat: Updates userRegion from backend.

JitsiConference.js

@@ -560,6 +560,8 @@ JitsiConference.prototype._init = function(options = {}) {
     // creates dominant speaker detection that works only in p2p mode
     this.p2pDominantSpeakerDetection = new P2PDominantSpeakerDetection(this);
 
+    // We keep this for some time, till all backends are updated to use
+    // the region from the http requests to prosody, after that we can drop it
     if (config && config.deploymentInfo && config.deploymentInfo.userRegion) {
         this.setLocalParticipantProperty(
             'region', config.deploymentInfo.userRegion);

modules/xmpp/ChatRoom.js

@@ -605,6 +605,10 @@ export default class ChatRoom extends Listenable {
                 member.features = this._extractFeatures(node);
                 break;
             }
+            case 'jitsi_participant_region': {
+                member.region = node.value;
+                break;
+            }
             case 'stat': {
                 const { attributes } = node;
 
@@ -652,6 +656,10 @@ export default class ChatRoom extends Listenable {
                     this.locked = true;
                 }
 
+                if (member.region && this.option?.deploymentInfo) {
+                    this.option.deploymentInfo.userRegion = member.region;
+                }
+
                 // Re-send presence in case any presence updates were added,
                 // but blocked from sending, during the join process.
                 // send the presence only if there was a modification after we had synced it