openStore(name) {
    console.log('tx:os');
    let store = new ObjectStore(this.transaction.objectStore(name));
    return store;
  }
/**
   * [open_store opens the given store for this transaction]
   * @param  {string} name [name of store to open]
   * @return {ObjectStore}      [Promes that resolves to the store or rejects on error]
   */
[open_store opens the given store for this transaction]
@param  {string} name [name of store to open]
@return {ObjectStore}      [Promes that resolves to the store or rejects on error]
[ open_store opens the given store for this transaction ] @param { string } name [ name of store to open ] @return { ObjectStore } [ Promes that resolves to the store or rejects on error ]
openStore(name) {
    console.log('tx:os');
    let store = new ObjectStore(this.transaction.objectStore(name));
    return store;
  }
openStore ( name ) { console . log ( 'tx:os' ) ; let store = new ObjectStore ( this . transaction . objectStore ( name ) ) ; return store ; }
[open_store opens the given store for this transaction]
 @param  {string} name [name of store to open]
 @return {ObjectStore}      [Promes that resolves to the store or rejects on error]
[ open_store opens the given store for this transaction ] @param { string } name [ name of store to open ] @return { ObjectStore } [ Promes that resolves to the store or rejects on error ]