Don't delete the locator win info

The locator win info is special because it is static, all the others are
created dynamically.

gdb/ChangeLog:

2020-11-29  Hannes Domani  <ssbssa@yahoo.de>

	PR tui/26973
	* tui/tui-layout.c (tui_apply_current_layout): Don't delete the
	static locator win info.

gdb/ChangeLog

@@ -1,3 +1,9 @@
+2020-11-29  Hannes Domani  <ssbssa@yahoo.de>
+
+	PR tui/26973
+	* tui/tui-layout.c (tui_apply_current_layout): Don't delete the
+	static locator win info.
+
 2020-11-28  Alex Richardson  <Alexander.Richardson@cl.cam.ac.uk>
 
 	* acincludde.m4 (GDB_AC_CHECK_BFD): Include string.h in the test

gdb/tui/tui-layout.c

@@ -98,13 +98,15 @@ tui_apply_current_layout ()
 
   /* Now delete any window that was not re-applied.  */
   tui_win_info *focus = tui_win_with_focus ();
+  tui_win_info *locator = tui_locator_win_info_ptr ();
   for (tui_win_info *win_info : saved_tui_windows)
     {
       if (!win_info->is_visible ())
 	{
 	  if (focus == win_info)
 	    tui_set_win_focus_to (tui_windows[0]);
-	  delete win_info;
+	  if (win_info != locator)
+	    delete win_info;
 	}
     }