[winswitch] windows xpra client CPU usage

[Thomas Esposito]

My Xpra-Launcher.exe process is ALWAYS using from 5% to 10% of my CPU
capacity, even when my X applications are TOTALLY idle (i.e. windows are
out of focus and/or no redrawing from X clients).

This is a HUGE increase in CPU usage (and heat generation) on my laptop
relative to when I'm just doing simple browsing and email. For example, if
i'm just browsing and reading/writing email, my total CPU usage stays under
1% to 2% and the laptop stays cool with the fan off. If I add the Xpra
client to this, even though I'm not interacting with the X application
windows and they are not redrawing, my laptop starts getting hot and the
fan turns on. Note this is only with a single X application window running.

In comparison, the TigerVNC viewer and x2go CPU usage is effectively 0% if
the windows are not updating.