Delete database on logout. DI a SyncAccumulator. Log uncaught errors

src/Lifecycle.js

@@ -329,10 +329,21 @@ export function startMatrixClient() {
  */
 export function onLoggedOut() {
     _clearLocalStorage();
+    _clearIndexedDB();
     stopMatrixClient();
     dis.dispatch({action: 'on_logged_out'});
 }
 
+function _clearIndexedDB() {
+    // remove indexeddb instances
+    if (!window.indexedDB) {
+        return;
+    }
+    console.log("Clearing indexeddb");
+    window.indexedDB.deleteDatabase("matrix-js-sdk");
+    window.indexedDB.deleteDatabase("logs");
+}
+
 function _clearLocalStorage() {
     if (!window.localStorage) {
         return;