Fix scrim opacity in the brightness mirror

ScrimController should be the only owner of scrim views.
This enables up to have better control over their opacities
and when they should fade in and out.

Test: visual
Change-Id: Ie3a1e1b4cc32e7998abe221a5c08eda2a8a2e6c0
Fixes: 38430977
3 files changed