[GraphicsEnvironment] Add whitelist support.

This patch adds the ability to load whitelist from updatable graphcis driver
apk. Typically a whitelist is part of the graphics driver apk, and the name is
set by overwriting ro.gfx.driver.whitelist.0

BUG: 117241379
Test: Build, flash and boot, whitelist an app and verify.
Change-Id: Ie36ca0173a90a8e48acaca2979ab64bbf92eeaed
Merged-In: Ie36ca0173a90a8e48acaca2979ab64bbf92eeaed