Since the paste object is pasted in the active collection, and not on
its original one, we need to flush/calculate the new collection base
settings (visibility, selectability, ...).
DEG_id_tag_update() for the scene now. Though it may be better to tag
only the object specific IDs in the future.
Note for users
==============
The active_layer option used for the filebrowser operators is now called
active_collection.
If there is no collections in the scenelayer or if this option is not selected
we automatically create a new collection for the new objects.
This is the same behaviour of trying to add a new object when there is
no collection.
Note for developers
===================
For those cases I moved the object user count handling from readfile to
the scene collection system. It's working fine for those, but we still
need to re-visit this for Add objects, and Duplicate - In those cases
the usercount is 2 when it should be 1.
Reviewers: mont29, sergey
Differential Revision: https://developer.blender.org/D2686
Issue here was that py API code was keeping references (pointers) to the
liniked data-blocks, which can actually be duplicated and then deleted
during the 'make local' process...
Would have like to find a better way than passing optional GHash to get
the oldid->newid mapping, but could not think of a better idea.
Uses similar way of storing temp data as object copy paste, just
uses different read entrypoint which does not modify current bmain.
This gives ability to easily copy-paste poses from one blender to
another one.
Hopefully doesn't introduce user-measurable differences.
Request from Peer here in the studio.
Reviewers: mont29
Reviewed By: mont29
Subscribers: hjalti, fsiddi
Differential Revision: https://developer.blender.org/D2229
