Force snapshot update when requested transform changes from invalid to valid

An early out in snapshot builder prevents parent properties from being propagated to children when the parent is hidden (e.g. due to invalid transform).
So we need to force update children snapshots when the parent becomes visible (i.e. transform becomes valid).

I tested removing the early out but the added benchmark takes 2us longer.

Bug: 319757092
Flag: EXEMPT bug fix
Test: atest libsurfaceflinger_unittests
Change-Id: I9c9a996bbc3de4e7f8cbfc947a99cdccae5090b9