Bugfix: Deleting backward selected text was getting stuck on redo.

Selections were not correctly preserved through undo/redo operations causing unexpected behaviour.

source/blender/blenkernel/intern/text.c

@@ -1821,6 +1821,12 @@ void txt_do_undo(Text *text)
 			
 			break;
 	}
+
+	/* next undo step may need evaluating */
+	if (text->undo_pos>=0 && text->undo_buf[text->undo_pos] == UNDO_STO) {
+		txt_do_undo(text);
+		txt_do_redo(text); /* selections need restoring */
+	}
 	
 	undoing= 0;	
 }
@@ -1895,7 +1901,7 @@ void txt_do_redo(Text *text)
 
 		case UNDO_SWAP:
 			txt_curs_swap(text);
-			txt_do_undo(text); /* swaps should appear transparent a*/
+			txt_do_redo(text); /* swaps should appear transparent a*/
 			break;
 			
 		case UNDO_CTO: