[I'd also be willing to bet money that this would barely have troubled the media had a few journalists not been fishing for B787 issues i nthe wake of the battery problems...
Well the FAA did get concerned. And it is still NOT clear if only one continuous run generator/power system/ground power connection for that time would trip ALL off line.
The fact that a ( simple ? ) ( single / ) counter could trip ALL systems ( including the APU ( total 6 generators ) off line until some sort of ground access reset doesn't say much for redundancy or safety.
And while the RAT could keep the controls running, it is NOT clear if engines could be restarted [takes electrical along with windmilling ( air start ) ]
Granted it is very very very unlikely- but the probibility and possibility is NOT ZERO.