proper use of QFlags

[René J. V. Bertin]

Marco Martin wrote:

>> Am I right that the argument `QFlags<State> state` should simply be `State
>> state`?
> 
> can you do a phab review about it?

Of course, but that seemed a bit overkill if this is an evident error, or if 
ultimately the runtime behaviour remains the same.

I understand from a diagonal read that QFlags is mostly an "inconvenience" class 
(pun intended) to impose stricter syntax rules than the language standard allows 
- and the errors raised under Qt 5.9 are simply because of additional asserts. 
Is that an overly reductionist summary?

R