X11: Match new extcmd immediately if no match was found

When entering an extended command, allow the user just type
and match a new command immediately, if no match was found,
instead of needing to wait the 2.5 seconds.

win/X11/winmisc.c

@@ -716,6 +716,7 @@ Cardinal *num_params;
 {
     char ch;
     int i;
+    int pass;
     XKeyEvent *xkey = (XKeyEvent *) event;
 
     nhUse(w);
@@ -768,6 +769,16 @@ Cardinal *num_params;
     if (ec_nchars >= EC_NCHARS)
         ec_nchars = EC_NCHARS - 1; /* don't overflow */
 
+    for (pass = 0; pass < 2; pass++) {
+        if (pass == 1) {
+            /* first pass finished, but no matching command was found */
+            /* start a new one with the last char entered */
+            if (extended_command_selected >= 0)
+                swap_fg_bg(extended_commands[extended_command_selected]);
+            extended_command_selected = -1; /* dismiss */
+            ec_chars[0] = ec_chars[ec_nchars-1];
+            ec_nchars = 1;
+        }
         for (i = 0; extcmdlist[i].ef_txt; i++) {
             if (extcmdlist[i].ef_txt[0] == '?')
                 continue;
@@ -781,7 +792,8 @@ Cardinal *num_params;
                     extended_command_selected = i;
                     swap_fg_bg(extended_commands[extended_command_selected]);
                 }
-            break;
+                return;
+            }
         }
     }
 }