0faf2a058e
After using the Purge Unused Data operator, hovering mouse over outliner makes outliner tree dirty as the tree is not being rebuilt. The operator is defined in python which calls `ANIM_armature_bonecoll_remove`. Add notifier in that function code so that `outliner_main_region_listener`will tag the outliner region for full redraw. Pull Request: https://projects.blender.org/blender/blender/pulls/140256