Users could change the master collection flags, but they should not.
That would not effectively affect the master collection objects
(depsgraph flag evaluation ignores master collection flags).
However we use the layer collection flags of the parent collection when creating
a new child collection.
We *could* solve this differently by creating a new RNA type for the
master collection (and layer collection) and hook this with rna refine.
But this patch seems to work well enough and it is simpler.
Reviewers: brecht
Differential Revision: https://developer.blender.org/D4981
d0258abdd7