FRE-600: Fix code review blockers

- Consolidated duplicate UndoManagers to single instance
- Fixed connection promise to only resolve on 'connected' status
- Fixed WebSocketProvider import (WebsocketProvider)
- Added proper doc.destroy() cleanup
- Renamed isPresenceInitialized property to avoid conflict

Co-Authored-By: Paperclip <noreply@paperclip.ing>

node_modules/core-js/internals/to-object.js

@@ -0,0 +1,10 @@
+'use strict';
+var requireObjectCoercible = require('../internals/require-object-coercible');
+
+var $Object = Object;
+
+// `ToObject` abstract operation
+// https://tc39.es/ecma262/#sec-toobject
+module.exports = function (argument) {
+  return $Object(requireObjectCoercible(argument));
+};