updating progress to user during long handler

[Kay C Lan]

oops, hit Send accidentally.

the above prevents me accidentally stacking lock screen and means I'm
only ever 1 unlock screen away from screen updates.

I think the preOpenStack/Card messaged automatically locks the screen
for you so their purpose can be achieved - positioning and preparing
your stack/card's appearance with default values etc prior to actual
display. It's neater and faster that way. If you removed the lock
screen you may be slowing things down.