gecko-dev/dom/indexedDB/test/browser_permissionsWorker.js

/* eslint-env worker */

onmessage = function(e) {
  var request = indexedDB.open(e.data, { version: 1,
                                         storage: "persistent" });
  request.onsuccess = function(event) {
    postMessage({ status: "success",
                  isIDBDatabase: (event.target.result instanceof IDBDatabase) });
  };

  request.onerror = function(event) {
    postMessage({ status: "error", error: event.target.error.name });
  };
};