Reduce padding below small, bold digital clock.

The grow transition looks bad due to clipping of the
text clock, but it is taking too long to understand the
issue. So, I want to get this padding change in and the
transition polish can follow.

Bug: 130223602
Test: visual -- look at AOD with music playing
Change-Id: I28cfecefeea55f49ee7843f0b1f07a206852dc54