Fix WidgetStore wrongly hanging onto old Widget definitions during removal

Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>

src/stores/WidgetStore.ts

@@ -122,6 +122,15 @@ export default class WidgetStore extends AsyncStoreWithClient<IState> {
         if (!room) return;
         const roomInfo = this.roomMap.get(room.roomId);
         roomInfo.widgets = [];
+
+        // first clean out old widgets from the map which originate from this room
+        // otherwise we are out of sync with the rest of the app with stale widget events during removal
+        Array.from(this.widgetMap.values()).forEach(app => {
+            if (app.roomId === room.roomId) {
+                this.widgetMap.delete(app.id);
+            }
+        });
+
         this.generateApps(room).forEach(app => {
             this.widgetMap.set(app.id, app);
             roomInfo.widgets.push(app);