Merge branch 'master' into blender2.8

- Undo that changes modes currently asserts,
  since undo is now screen data.

  Most likely we will change how object mode and workspaces work
  since it's not practical/maintainable at the moment.

- Removed view_layer from particle settings
  (wasn't needed and complicated undo).

source/blender/editors/mesh/editmesh_utils.c

@@ -43,7 +43,6 @@
 
 #include "BKE_DerivedMesh.h"
 #include "BKE_context.h"
-#include "BKE_global.h"
 #include "BKE_main.h"
 #include "BKE_mesh.h"
 #include "BKE_mesh_mapping.h"