[FIX] web_editor: ensure the bus is available

In the frontend of project, the bus service is not available.
Since #129785, the test `portal_project_sharing_tour` crash
because `this.busService` is `undefined` when we try to access
it in `Wysiwyg.setupCollaboration`.

task-3434068

closes odoo/odoo#133477

Related: odoo/enterprise#46479
Signed-off-by: David Monjoie (dmo) <dmo@odoo.com>

addons/web_editor/static/src/js/wysiwyg/wysiwyg.js

@@ -325,10 +325,7 @@ export class Wysiwyg extends Component {
         const powerboxOptions = this._getPowerboxOptions();
 
         let editorCollaborationOptions;
-        if (
-            options.collaborationChannel &&
-            this._hasICEServers()
-        ) {
+        if (this._isCollaborationEnabled(options)) {
             editorCollaborationOptions = this.setupCollaboration(options.collaborationChannel);
             if (this.options.collaborativeTrigger === 'start') {
                 this._joinPeerToPeer();
@@ -2878,7 +2875,7 @@ export class Wysiwyg extends Component {
         this._stopPeerToPeer();
         this._rulesCache = undefined; // Reset the cache of rules.
         // If there is no collaborationResId, the record has been deleted.
-        if (!collaborationChannel || !collaborationChannel.collaborationResId) {
+        if (!this._isCollaborationEnabled(this.options)) {
             this.setValue(value);
             this.odooEditor.historyReset();
             return;
@@ -2931,6 +2928,9 @@ export class Wysiwyg extends Component {
         // Hack: check if mail module is installed.
         return session.notification_type;
     }
+    _isCollaborationEnabled(options) {
+        return options.collaborationChannel && options.collaborationChannel.collaborationResId && this._hasICEServers() && this.busService;
+    }
 
     /**
      * Saves a base64 encoded image as an attachment.