Hide the notification tray carrier label during and not after flip animation

It's possible for the user to have enough quick settings tiles to cover
the carrier label during the flip animation. This looks a bit strange,
so hide the carrier label during a flip.

Change-Id: I6dd38d5642a1d49c079ecdc4a7e904be6c26454c
Merge "Hide the notification tray carrier label during and not after flip animation" into cm-11.0