Add dataLoss property to IDB's upgradeneeded event

LayoutTests/storage/indexeddb/resources/data-corruption.js

 if (this.importScripts) {
     importScripts('../../../fast/js/resources/js-test-pre.js');
     importScripts('shared.js');
 }
 
 description("Test that data inserted into IndexedDB does not get corrupted on disk.");
 
 indexedDBTest(prepareDatabase, addData);
 function prepareDatabase()
 {
     db = event.target.result;
     debug("setVersionSuccess():");
+    shouldBeEqualToString("event.dataLoss", "none");

[jsbell, 2013/06/17 23:37:35]

You should also add a "'dataLoss' in XXXXX" case to resources/events.js

[dgrogan, 2013/06/17 23:52:14]

Done.

     self.trans = evalAndLog("trans = event.target.transaction");
     shouldBeNonNull("trans");
     trans.onabort = unexpectedAbortCallback;
 
     evalAndLog("db.createObjectStore('storeName')");
 }
 
 var testDate = new Date('February 24, 1955 12:00:08');
 
 function addData()
@@ skipping 12 matching lines @@
     var request = evalAndLog("request = transaction.objectStore('storeName').get('key')");
     request.onerror = unexpectedErrorCallback;
     request.onsuccess = doCheck;
 }
 
 function doCheck()
 {
     shouldBe("event.target.result.x.toString()", "testDate.toString()");
     finishJSTest();
 }