window-x11: Fix icon-change signal connection
window-x11: Fix icon-change signal connection

These were meant to be g_signal_connect_swapped instead of just standard
connections. This fixes setting an icon on a window not working, and a
critical warning when you try to do so.

clutter-project/mx,clutter-project/mx,jonnylamb/mx,pwithnall/mx,jonnylamb/mx,pwithnall/mx,jonnylamb/mx,pwithnall/mx,clutter-project/mx,pwithnall/mx,clutter-project/mx,jonnylamb/mx