Add GlowPadView extensions needed for lockscreen targets and nav ring.

Change-Id: I4f82fd3fe04ac16c6737d38b2473f2a533c5d326
Add back navigation ring customization.

Change-Id: Iebe4ec7c2519b85cfd5189d060444764a50f3cf6

Conflicts:
	core/java/android/provider/Settings.java
	core/res/res/values/symbols.xml