IndexedDB: Log exception messages

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

 Test IndexedDB Array-type keyPaths
 
 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-arrays.html"
 indexedDB.deleteDatabase(dbname)
 indexedDB.open(dbname)
 store = db.createObjectStore('store', {keyPath: ['a', 'b']})
 store.createIndex('index', ['c', 'd'])
 Expecting exception from db.createObjectStore('store-with-generator', {keyPath: ['a', 'b'], autoIncrement: true})
 PASS Exception was thrown.
 PASS code is DOMException.INVALID_ACCESS_ERR
+Exception message: The autoIncrement option was set but the keyPath option was empty or an array.
 Expecting exception from store.createIndex('index-multientry', ['e', 'f'], {multiEntry: true})
 PASS Exception was thrown.
 PASS code is DOMException.INVALID_ACCESS_ERR
+Exception message: The keyPath argument was an array and the multiEntry option is true.
 
 Empty arrays are not valid key paths:
 Expecting exception from db.createObjectStore('store-keypath-empty-array', {keyPath: []})
 PASS Exception was thrown.
 PASS code is DOMException.SYNTAX_ERR
+Exception message: The keyPath option is not a valid key path.
 Expecting exception from store.createIndex('index-keypath-empty-array', [])
 PASS Exception was thrown.
 PASS code is DOMException.SYNTAX_ERR
+Exception message: The keyPath argument contains an invalid key path.
 
 testKeyPaths():
 transaction = db.transaction(['store'], 'readwrite')
 store = transaction.objectStore('store')
 index = store.index('index')
 
 request = store.put({a: 1, b: 2, c: 3, d: 4})
 request = store.openCursor()
 cursor = request.result
 PASS cursor is non-null.
 PASS JSON.stringify(cursor.key) is "[1,2]"
 request = index.openCursor()
 cursor = request.result
 PASS cursor is non-null.
 PASS JSON.stringify(cursor.primaryKey) is "[1,2]"
 PASS JSON.stringify(cursor.key) is "[3,4]"
 PASS successfullyParsed is true
 
 TEST COMPLETE