Add white edgelights to AOSP

Moves most of the invocation code (as well as PerimeterPathGuide,
CornerPathRenderer, and EdgeLight) into base SystemUI. Shows
white edge lights coming in from the corners into the center, from
gesture or squeeze.

Bug: 132984557
Test: manual

Change-Id: Icbe611c3513f24f0ac13b68bd4d65f7cb4d402d6