Indexed DB: Remove vendor prefix removal from tests

LayoutTests/storage/indexeddb/keypath-edges-expected.txt

 Test IndexedDB keyPath edge cases
 
 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 = "keypath-edges.html"
 indexedDB.deleteDatabase(dbname)
 indexedDB.open(dbname)
 db.createObjectStore('store-with-path', {keyPath: 'foo'})
 db.createObjectStore('store-with-path-and-generator', {keyPath: 'foo', autoIncrement: true})
 
 testKeyPaths():
 transaction = db.transaction(['store-with-path'], 'readwrite')
 store = transaction.objectStore('store-with-path')
 
@@ skipping 51 matching lines @@
 PASS ename is 'DataError'
 Exception message: Failed to execute 'put' on 'IDBObjectStore': Evaluating the object store's key path yielded a value that is not a valid key.
 
 Key path resolves to a value that is valid key; should yield 'string' key, should succeed
 store.put({foo: 'zoo'})
 PASS store.put succeeded
 PASS successfullyParsed is true
 
 TEST COMPLETE