Fix for 2292713: Remove workaround that hides SlidingTab widget while internal...

Fix for 2292713: Remove workaround that hides SlidingTab widget while internal state is inconsistent.

The previous workaround for this race condition prevented glitches by postponing drawing the SlidingTab until the internal state was consistent.  Unfortunately, the InCallScreen seems to trigger this most of the time if the keyboard is open or the last application was in landscape mode.

Instead, we'll handle this separately in lockscreen.