[Home Controls] Fix sizing and color of chevron.

Set sizing to be material icon. It now looks like the arrow in QS. Also
set tintlist to be the same as the icon. Also, make sure to disable the
imageview when the icon is disabled. In this state, the icon is greyed
out.

Bug: 232250913
Test: Manual on large device. Sent screenshot for design to verify.
Change-Id: I61647c38e6e0d678fd876b5094b3bcf63947b2b9