IndexedDB: Log exception messages

LayoutTests/storage/indexeddb/database-closepending-flag-expected.txt

 Test IndexedDB IDBDatabase internal closePending flag
 
 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 = "database-closepending-flag.html"
 indexedDB.deleteDatabase(dbname)
 indexedDB.open(dbname)
 store = connection.createObjectStore('store')
 
 First, verify that the database connection is not closed:
 PASS transaction = connection.transaction('store') did not throw exception.
 
 Database closing steps
 "1. Set the internal closePending flag of connection to true."
 connection.close()
 Expecting exception from connection.transaction('store')
 PASS Exception was thrown.
 PASS code is DOMException.INVALID_STATE_ERR
 PASS ename is 'InvalidStateError'
+Exception message: The database connection is closing.
 "2. Wait for all transactions created using connection to complete. Once they are complete, connection is closed."
 transaction.oncomplete = testIDBDatabaseName
 
 IDBDatabase.name:
 "The function must return this name even if the closePending flag is set on the connection."
 PASS connection.name is dbname
 
 IDBDatabase.objectStoreNames:
 "Once the closePending flag is set on the connection, this function must return a snapshot of the list of names of the object stores taken at the time when the close method was called."
 request = indexedDB.open(dbname, 2)
 version_change_connection = request.result
 version_change_connection.createObjectStore('new_store')
 PASS version_change_connection.objectStoreNames.contains('new_store') is true
 PASS connection.objectStoreNames.contains('new_store') is false
 version_change_connection.close()
 
 IDBDatabase.transaction():
 "...if this method is called on a IDBDatabase instance where the closePending flag is set, a InvalidStateError exception must be thrown."
 Expecting exception from connection.transaction('store')
 PASS Exception was thrown.
 PASS code is DOMException.INVALID_STATE_ERR
 PASS ename is 'InvalidStateError'
+Exception message: The database connection is closing.
 
 "versionchange" transaction steps:
 "Fire a versionchange event at each object in openDatabases that is open. The event must not be fired on objects which has the closePending flag set."
 request = indexedDB.open(dbname)
 connection = request.result
 versionChangeWasFired = false
 connection.onversionchange = function () { versionChangeWasFired = true; }
 transaction = connection.transaction('store')
 connection.close()
 closePending is set, but active transaction will keep connection from closing
@@ skipping 12 matching lines @@
 transaction = connection.transaction('store')
 connection.close()
 closePending is set, but active transaction will keep connection from closing
 request = indexedDB.deleteDatabase(dbname)
 'blocked' event fired, letting transaction complete and connection close
 PASS versionChangeWasFired is false
 PASS successfullyParsed is true
 
 TEST COMPLETE