UI Improvements

Update the custom theme steps based on the latest spec:
 - Remove font name from custom font card
 - Don't use a card any more
 - Update the landscape layout for custom editor

Make the bottom full screen as speced for full gesture nav.

Bug: 129154138
Fixes: 130763683
Change-Id: Ie6191caed915ea6bfcfa255c541f55504d97c4d3