Add LocalStorageErrorEventListener

Add a way to listen to LocalStorage error events from element-web
and matrix-react-sdk in the same manner.

Related: element-hq/element-web#18423

src/store/local-storage-events-emitter.ts

@@ -0,0 +1,36 @@
+/*
+Copyright 2021 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { TypedEventEmitter } from "../models/typed-event-emitter";
+
+export enum LocalStorageErrors {
+    Global = 'Global',
+    SetItemError = 'setItem',
+    GetItemError = 'getItem',
+    RemoveItemError = 'removeItem',
+    ClearError = 'clear',
+    QuotaExceededError = 'QuotaExceededError'
+}
+
+/**
+ * Used in element-web as a temporary hack to handle all the localStorage errors on the highest level possible
+ * As of 15.11.2021 (DD/MM/YYYY) we're not properly handling local storage exceptions anywhere.
+ * This store, as an event emitter, is used to re-emit local storage exceptions so that we can handle them
+ * and show some kind of a "It's dead Jim" modal to the users, telling them that hey,
+ * maybe you should check out your disk, as it's probably dying and your session may die with it.
+ * See: https://github.com/vector-im/element-web/issues/18423
+ */
+export const localStorageErrorsEventsEmitter = new TypedEventEmitter<LocalStorageErrors>();