RAI: Always send the presence to enable RAI when leaving a MUC

Looking at the Prosody code, it appears to be cheap since
Prosody will do nothing if you're already registered and this works
around a bug in mod_muc_rai where events aren't fired for each resource
of the same joined nick joining or leaving the MUC.

spec/rai.js

@@ -190,7 +190,6 @@ describe("XEP-0437 Room Activity Indicators", function () {
         expect(_converse.session.get('rai_enabled_domains')).toBe(undefined);
 
         const muc_jid = 'lounge@montague.lit';
-        const muc_domain = Strophe.getDomainFromJid(muc_jid);
         await mock.openAndEnterChatRoom(_converse, muc_jid, 'romeo');
         const view = _converse.api.chatviews.get(muc_jid);
         expect(view.model.get('hidden')).toBe(false);
@@ -212,9 +211,6 @@ describe("XEP-0437 Room Activity Indicators", function () {
                 `<rai xmlns="urn:xmpp:rai:0"/>`+
             `</presence>`
         );
-        expect(view.model.session.get('connection_status')).toBe(converse.ROOMSTATUS.DISCONNECTED);
-                expect(_converse.session.get('rai_enabled_domains')).toBe(` ${muc_domain}`);
-
         // If an error presence with "resource-constraint" is returned, we rejoin
         const activity_stanza = u.toStanza(`
             <presence type="error" from="${Strophe.getDomainFromJid(muc_jid)}">
@@ -224,8 +220,6 @@ describe("XEP-0437 Room Activity Indicators", function () {
         _converse.connection._dataRecv(mock.createRequest(activity_stanza));
 
         await u.waitUntil(() => view.model.session.get('connection_status') === converse.ROOMSTATUS.CONNECTING);
-
-        expect(_converse.session.get('rai_enabled_domains')).toBe(' ');
         done();
     }));
 

src/headless/plugins/muc/index.js

@@ -432,8 +432,6 @@ converse.plugins.add('converse-muc', {
             api.listen.on('reconnected', registerDirectInvitationHandler);
         }
 
-        api.listen.on('reconnected', () => _converse.session.save('rai_enabled_domains', ''));
-
         api.listen.on('beforeTearDown', () => {
             const groupchats = _converse.chatboxes.where({ 'type': _converse.CHATROOMS_TYPE });
             groupchats.forEach(muc =>

src/headless/plugins/muc/muc.js

@@ -211,12 +211,8 @@ const ChatRoomMixin = {
      */
     enableRAI () {
         if (api.settings.get('muc_subscribe_to_rai')) {
-            const rai_enabled = _converse.session.get('rai_enabled_domains') || '';
             const muc_domain = Strophe.getDomainFromJid(this.get('jid'));
-            if (!rai_enabled.includes(muc_domain)) {
-                api.user.presence.send(null, muc_domain, null, $build('rai', { 'xmlns': Strophe.NS.RAI }));
-                _converse.session.save({ 'rai_enabled_domains': `${rai_enabled} ${muc_domain}` });
-            }
+            api.user.presence.send(null, muc_domain, null, $build('rai', { 'xmlns': Strophe.NS.RAI }));
         }
     },
 
@@ -2250,15 +2246,9 @@ const ChatRoomMixin = {
             if (error?.getAttribute('type') === 'wait' && error?.querySelector('resource-constraint')) {
                 // If we get a <resource-constraint> error, we assume it's in context of XEP-0437 RAI.
                 // We remove this MUC's host from the list of enabled domains and rejoin the MUC.
-                const rai_enabled = _converse.session.get('rai_enabled_domains') || '';
                 const muc_domain = Strophe.getDomainFromJid(this.get('jid'));
-                if (rai_enabled.includes(muc_domain)) {
-                    const regex = new RegExp(muc_domain, 'g');
-                    _converse.session.save({ 'rai_enabled_domains': rai_enabled.replace(regex, '') });
-
-                    if (this.session.get('connection_status') === converse.ROOMSTATUS.DISCONNECTED) {
-                        this.rejoin();
-                    }
+                if (this.session.get('connection_status') === converse.ROOMSTATUS.DISCONNECTED) {
+                    this.rejoin();
                 }
             }
         }