打包微端时遇到的奇怪加载问题

try {
  var indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndexedDB || window.msIndexedDB;
  var openRequest = indexedDB.open(databaseName);
  openRequest.onupgradeneeded = function (e) {
    initDatabase(e.target.result); //加上这句就好了
    var objectStore = e.target.result.createObjectStore(store, { keyPath: "url" });
    ["version", "company", "product", "updated", "revalidated", "accessed"].forEach(function (index) { objectStore.createIndex(index, index); });
  };
  openRequest.onsuccess = function (e) { initDatabase(e.target.result); };
  openRequest.onerror = function (e) { initDatabase(null); };
  setTimeout(openRequest.onerror, 1000);
} catch (e) {
  initDatabase(null);
}