Indexed DB: Remove vendor prefix removal from tests

LayoutTests/storage/indexeddb/request-result-cache-expected.txt

 Verify that a request's result is dirtied when a cursor is continued
 
 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 = "request-result-cache.html"
 indexedDB.deleteDatabase(dbname)
 indexedDB.open(dbname)
 
 prepareDatabase():
 db = event.target.result
 store = db.createObjectStore('store')
 
 onOpen():
 db = event.target.result
 tx = db.transaction('store')
 store = tx.objectStore('store')
 cursorRequest = store.openCursor()
 
 cursorRequestSuccess():
 cursor = cursorRequest.result
 cursor.continue()
 Expecting exception from cursorRequest.result
 PASS Exception was thrown.
 PASS code is DOMException.INVALID_STATE_ERR
 PASS ename is 'InvalidStateError'
 Exception message: Failed to read the 'result' property from 'IDBRequest': The request has not finished.
 
 cursorRequestSuccess():
 PASS successfullyParsed is true
 
 TEST COMPLETE