bug#18545: 24.4.50: Bug - forward-line inside with-selected-window

[Eli Zaretskii]

> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 18545@debbugs.gnu.org
> 
> This works OK in v24.3, so it's a regression.

The patch below seems to fix the problem.  It catches the situation
where try_window failed to redisplay the window, in which case we
shouldn't "goto done" as if we succeeded.


=== modified file 'src/xdisp.c'
--- src/xdisp.c 2014-09-18 15:10:33 +0000
+++ src/xdisp.c 2014-09-25 15:15:42 +0000
@@ -16293,6 +16293,11 @@ redisplay_window (Lisp_Object window, bo
            }
          */
        }
+      else if (w->cursor.vpos < 0)
+       {
+         clear_glyph_matrix (w->desired_matrix);
+         goto try_to_scroll;
+       }
 
 #ifdef GLYPH_DEBUG
       debug_method_add (w, "forced window start");