Indexed DB: Remove vendor prefix removal from tests

LayoutTests/storage/indexeddb/cursor-cast-expected.txt

 Ensure cursor wrappers are created correctly.
 
 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 = "cursor-cast.html"
 indexedDB.deleteDatabase(dbname)
 indexedDB.open(dbname)
 
 prepareDatabase():
 db = event.target.result
 store = db.createObjectStore('store')
 store.put(0, 0)
 
 verifyWrappers():
 db = event.target.result
 tx = db.transaction('store', 'readwrite')
 request = tx.objectStore('store').openCursor()
 
 onOpenCursorSuccess():
 cursor = event.target.result
 request = cursor.update(1)
 
 onUpdateSuccess():
 cursor = null
 PASS request.source.toString() is "[object IDBCursorWithValue]"
 PASS successfullyParsed is true
 
 TEST COMPLETE