Using latest fixes from XPCKit subrepository
Safeguard against usage of NSPopover class in OS versions prior to 10.7
Establish an explicit autorelease pool when asynchronously requesting service from a parser

Parser operations are usually expensive and dispatch queue's default autorelease pool is not being drained after execution of every queued block

Note: there is also vague hope that this will fix some strange bugs associated with the use of archiver/unarchiver within this function.