Indexed DB: Remove vendor prefix removal from tests

LayoutTests/storage/indexeddb/mozilla/object-identity-expected.txt

 Test IndexedDB: object identity
 
 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 = "object-identity.html"
 indexedDB.deleteDatabase(dbname)
 indexedDB.open(dbname)
 transaction = event.target.transaction;
 objectStore1 = db.createObjectStore('foo');
 objectStore2 = transaction.objectStore('foo');
 PASS objectStore1 === objectStore2 is true
 index1 = objectStore1.createIndex('bar', 'key');
 index2 = objectStore2.index('bar');
 PASS index1 === index2 is true
 transaction = db.transaction('foo');
 objectStore3 = transaction.objectStore('foo');
 objectStore3.someProperty = 'xyz'
 objectStore4 = transaction.objectStore('foo');
 PASS objectStore3 === objectStore4 is true
 PASS objectStore4.someProperty is "xyz"
 PASS objectStore3 === objectStore1 is false
 PASS objectStore4 === objectStore2 is false
 index3 = objectStore3.index('bar');
 index4 = objectStore4.index('bar');
 PASS index3 === index4 is true
 PASS index3 === index1 is false
 PASS index4 === index2 is false
 PASS successfullyParsed is true
 
 TEST COMPLETE