Grid adjustments, specifically for Ryu.

> Less than 14% of the screen is used for left/right workspace padding.
  (To be clear, this means 7% for the left and 7% for the right.)
> Hotseat icons are the same size as workspace icons.
> Far left and right hotseat edges line up with workspace edges.
> All Apps button is scaled down 8dp.

Bug: 24003478

Change-Id: Idb057ab0f6ba29e7fd93feac7573ca2e07c7e839