src/store/indexeddb-local-backend.js
function LocalIndexedDBStoreBackend(
    indexedDBInterface, dbName,
) {
    this.indexedDB = indexedDBInterface;
    this._dbName = "matrix-js-sdk:" + (dbName || "default");
    this.db = null;
    this._disconnected = true;
    this._syncAccumulator = new SyncAccumulator();
    this._isNewlyCreated = false;
}
function LocalIndexedDBStoreBackend(
    indexedDBInterface, dbName,
) {
    this.indexedDB = indexedDBInterface;
    this._dbName = "matrix-js-sdk:" + (dbName || "default");
    this.db = null;
    this._disconnected = true;
    this._syncAccumulator = new SyncAccumulator();
    this._isNewlyCreated = false;
}
function LocalIndexedDBStoreBackend ( indexedDBInterface , dbName , ) { this . indexedDB = indexedDBInterface ; this . _dbName = "matrix-js-sdk:" + ( dbName || "default" ) ; this . db = null ; this . _disconnected = true ; this . _syncAccumulator = new SyncAccumulator ( ) ; this . _isNewlyCreated = false ; }
Does the actual reading from and writing to the indexeddb

Construct a new Indexed Database store backend. This requires a call to
<code>connect()</code> before this store can be used.
@constructor
@param {Object} indexedDBInterface The Indexed DB interface e.g
<code>window.indexedDB</code>
@param {string=} dbName Optional database name. The same name must be used
to open the same database.
Does the actual reading from and writing to the indexeddb