Interesting theory but this 777 (manufactured in 2002) wasn’t equipped with that.
It seems that most Boeing aircraft since 1995 or 1996 were retrofitted with the B.U.A.P. The FAA and NTSB are supposedly aware of this fact.
I don’t have a very good source right now. There was a commercial airline Pilot, (former) U.S. Marine Field McConnell, who obtained this information in discovery documents during the course of a federal lawsuit versus ALPA.
I did find these sources: http://www.abeldanger.net/
https://www.youtube.com/watch?feature=player_embedded&v=UVV8vwwarv8&list=UURGIwParDeoovmhflq9Agmg
http://voiceofrussia.com/us/2014_03_18/Stealth-Technology-Seizure-Behind-MH370-Disappearance-5715/
Yeah, the third source is McConnell via Voice of Russia. I hate it when that happens. I think the information is worth further verification though.