vnc: Make ledstate comparison before modifiers updated

The ledstate should be compared before modifiers updated,
otherwise the ledstate would be the same as current_led_state.

Reported-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Lei Li <lilei@linux.vnet.ibm.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1368606040-11950-1-git-send-email-lilei@linux.vnet.ibm.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

ui/vnc.c

@@ -1601,6 +1601,7 @@ static void kbd_leds(void *opaque, int ledstate)
 {
     VncState *vs = opaque;
     int caps, num, scr;
+    bool has_changed = (ledstate != current_led_state(vs));
 
     caps = ledstate & QEMU_CAPS_LOCK_LED ? 1 : 0;
     num  = ledstate & QEMU_NUM_LOCK_LED  ? 1 : 0;
@@ -1617,7 +1618,7 @@ static void kbd_leds(void *opaque, int ledstate)
     }
 
     /* Sending the current led state message to the client */
-    if (ledstate != current_led_state(vs)) {
+    if (has_changed) {
         vnc_led_state_change(vs);
     }
 }