Fix T56172 Accessing COW data from RNA - Dimension

Also fixes T55769 Dimension Not properly work
and T56064 Blender crashes on selecting text-object

We decided to go to the easy way in the end, simply enforcing computing
BBox of all objects when using 'active' depsgraph, and copying back to
orig object (same as transform matrix, etc.).

source/blender/blenkernel/intern/object_update.c

@@ -149,6 +149,14 @@ void BKE_object_eval_done(Depsgraph *depsgraph, Object *ob)
 		copy_m4_m4(ob_orig->constinv, ob->constinv);
 		ob_orig->transflag = ob->transflag;
 		ob_orig->flag = ob->flag;
+
+		BoundBox *bb = BKE_object_boundbox_get(ob);
+		if (bb != NULL) {
+			if (ob_orig->bb == NULL) {
+				ob_orig->bb = MEM_mallocN(sizeof(*ob_orig->bb), __func__);
+			}
+			*ob_orig->bb = *bb;
+		}
 	}
 }