Bugfix #26891

Recoded the move-to-layer popup to wait for execution of operator until you 
press Enter or OK button.
That excludes undo/redo, which makes it faster for many too.

(note the menu is all hotkey driven, so it's MKEY, <number>, Enter)

Also fixed: missing MEM_free in this popup type.

source/blender/editors/object/object_relations.c

@@ -1233,7 +1233,7 @@ static int move_to_layer_invoke(bContext *C, wmOperator *op, wmEvent *event)
 	}
 	else {
 		move_to_layer_init(C, op);
-		return WM_operator_props_popup(C, op, event);
+		return WM_operator_props_dialog_popup(C, op, 260, 30);
 	}
 }
 

source/blender/windowmanager/intern/wm_operators.c

@@ -1186,6 +1186,8 @@ static void wm_operator_ui_popup_ok(struct bContext *C, void *arg, int retval)
 
 	if (op && retval > 0)
 		WM_operator_call(C, op);
+	
+	MEM_freeN(data);
 }
 
 int WM_operator_ui_popup(bContext *C, wmOperator *op, int width, int height)