22bda12af7
Area "close" operation is actually an area merge of some area into the one being closed. This means that screen->active_region will be pointing at deallocated RAM. Normally not noticed because active_region is set very quickly to the new area, but error nonetheless and noticed by ASAN. This PR sets the screen->active_region to null when merges change the active area. Pull Request: https://projects.blender.org/blender/blender/pulls/131994