tweaks: reorder a case item, to have SPLIT_BEGIN always before SPLIT_END

Also, avoid two superfluous assignments of a message, as they get
overwritten immediately by other ones, and later with the same.

Furthermore, remove two pointless placements of the cursor.  Any
necessary placements are handled by the actual adding of data and
the breaking of lines in the ADD and ENTER items.

src/text.c

@@ -580,15 +580,14 @@ void do_undo(void)
 		goto_line_posx(u->head_lineno, u->head_x);
 		break;
 #ifdef ENABLE_WRAPPING
+	case SPLIT_BEGIN:
+		undidmsg = _("addition");
+		break;
 	case SPLIT_END:
-		goto_line_posx(u->head_lineno, u->head_x);
 		openfile->current_undo = openfile->current_undo->next;
 		while (openfile->current_undo->type != SPLIT_BEGIN)
 			do_undo();
 		u = openfile->current_undo;
-		/* Fall-through. */
-	case SPLIT_BEGIN:
-		undidmsg = _("addition");
 		break;
 #endif
 	case ZAP:
@@ -746,13 +745,12 @@ void do_redo(void)
 		break;
 #ifdef ENABLE_WRAPPING
 	case SPLIT_BEGIN:
-		goto_line_posx(u->head_lineno, u->head_x);
 		openfile->current_undo = u;
 		while (openfile->current_undo->type != SPLIT_END)
 			do_redo();
 		u = openfile->current_undo;
 		goto_line_posx(u->head_lineno, u->head_x);
-		/* Fall-through. */
+		break;
 	case SPLIT_END:
 		redidmsg = _("addition");
 		break;
@@ -1121,6 +1119,7 @@ void add_undo(undo_type action, const char *message)
 	 * SPLIT_BEGIN item underneath that action's undo item.  Otherwise,
 	 * just add the new item to the top of the undo stack. */
 	if (u->type == SPLIT_BEGIN) {
+		action = openfile->undotop->type;
 		u->wassize = openfile->undotop->wassize;
 		u->next = openfile->undotop->next;
 		openfile->undotop->next = u;
@@ -1177,8 +1176,6 @@ void add_undo(undo_type action, const char *message)
 		break;
 #ifdef ENABLE_WRAPPING
 	case SPLIT_BEGIN:
-		action = openfile->undotop->type;
-		break;
 	case SPLIT_END:
 		break;
 #endif