var port;
self.addEventListener('message', function(e) {
    var message = e.data;
    if ('port' in message)
      doIndexedDBTest(message.port);
  });

function doIndexedDBTest(port) {
  var delete_request = indexedDB.deleteDatabase('db');
  delete_request.onsuccess = function() {
    var open_request = indexedDB.open('db');
    open_request.onupgradeneeded = function() {
      var db = open_request.result;
      db.createObjectStore('store');
    };
    open_request.onsuccess = function() {
      var db = open_request.result;
      var tx = db.transaction('store', 'readwrite');
      var store = tx.objectStore('store');
      store.put('value', 'key');
      tx.oncomplete = function() {
        port.postMessage('done');
      };
    };
  };
}