New glow spec

Combination of a linear gradient, clipped around a radial gradient, and
distorted with simplex noise.

Fixes: 416168362
Flag: com.android.systemui.enable_underlay
Test: atest AmbientCueContainerScreenshotTest
Test: visual
Change-Id: I456e65780bd7aea747be9851a7f17b14155b6c03