Blender Git Loki

Split base flags on own and collection-defined

This allows to update base flags to a proper state then object's restriction
flags are changed, without requiring to re-evaluate an entire tree of flags.

Some old unused flags are were removed by this change, and also disabling
menu items might not work the same as before. This is something we can bring
back if it's really needed (the way how flags are handled did change since
that interface code was done anyway, so code was looking weird anyway).

Reviewers: brecht

Differential Revision: https://developer.blender.org/D4420