Blender Git Loki

Outliner: support toggling non-active edit/pose mode objects

Support switching non-active objects in/out of a mode from the outliner.

- This allows users to change which objects are in a mode w/o
having to exit the mode and change seleciton.
- Changing the mode of the active object applies to all other objects.
- By convention setting a mode selects, removing de-selects,
this is done for convenience so switching to a mode from object mode
maintains the set of objects in the current mode.

See: T55246