Indexed DB: Remove vendor prefix removal from tests

LayoutTests/storage/indexeddb/factory-deletedatabase-expected.txt

 Test IndexedDB's indexedDB.deleteDatabase().
 
 On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
 
 
-indexedDB = self.indexedDB || self.webkitIndexedDB || self.mozIndexedDB || self.msIndexedDB || self.OIndexedDB;
-
 dbname = "factory-deletedatabase.html"
 indexedDB.deleteDatabase(dbname)
 indexedDB.open(dbname)
 store = db.createObjectStore('storeName', null)
 store.createIndex('indexName', '')
 PASS store.indexNames.contains('indexName') is true
 store.add('value', 'key')
 db.transaction('storeName', 'readwrite')
 store = transaction.objectStore('storeName')
 store.get('key')
 PASS event.target.result is "value"
 db.close()
 indexedDB.open(dbname, 2)
 db = event.target.result
 request = indexedDB.deleteDatabase(dbname)
 db.close()
 PASS request.result is undefined.
 indexedDB.open(dbname, 3)
 db = event.target.result
 PASS db.objectStoreNames.length is 0
 PASS successfullyParsed is true
 
 TEST COMPLETE