Fixed clipping of qs focus state

Ripple drawable uses some custom draw logic that clips its layers
should they attempt to draw outside of its bound. So I've moved focus
layer of qs tile background to overlay - now focus state will be
rendered as an overlay of the view, avoiding any issues with clipping.

Test: Manual test - go/sysui-pkt-manual-testing
Fixes: 340897219
Flag: ACONFIG com.android.systemui.qs_tile_focus_state TRUNKFOOD
Change-Id: I287cec0ebec97c2494b14ce6c6fde20baf57dd92