Changed the landscape experience of quick settings

When introducing Media into quick settings, the landscape
experience never really worked well. The music player
would be cut off on the bottom and users could never
reach their playback controls.
Instead of the vertical layout, we're now rendering
quick settings side by side with the player.

Using some densities, this could still be too large,
so we're also introducing a scrollview for the
expanded quick settings.
This also makes sure all the paddings and spacings
are up to spec.

This also fixes behavior where a user could still collapse
the panel while the user switcher was showing.

Bug: 154332040
Test: atest SystemUITests
Change-Id: I3b8babc2cc6a91e19824b67f043aa5044dc370b9