gud-refresh recentering bugs

[Al Petrofsky]

In emacs 21.1,

If I'm in the buffer containing the gud arrow, but more than a
screenful away from the arrow, C-x C-a C-l fails to move me to the
arrow line.

Also, if I'm in a full-frame window displaying some other buffer, C-x
C-a C-l correctly brings up the arrow buffer in the lower half of the
frame, but it screws up the window-start and point of the upper half.

The fix is to move the call to `recenter' from the start of
gud-refresh to the end:

--- gud.el.~1.153.~     Fri Jan 18 10:57:20 2002
+++ gud.el      Sun Feb  3 20:30:24 2002
@@ -2512,9 +2512,9 @@
 (defun gud-refresh (&optional arg)
   "Fix up a possibly garbled display, and redraw the arrow."
   (interactive "P")
-  (recenter arg)
   (or gud-last-frame (setq gud-last-frame gud-last-last-frame))
-  (gud-display-frame))
+  (gud-display-frame)
+  (recenter arg))
 
 ;;; Code for parsing expressions out of C code.  The single entry point is
 ;;; find-c-expr, which tries to return an lvalue expression from around point.