Keep the old method for backward compatible

Use keep to avoid compiler remove these methods when no callers.
Also use this annotation as a reminder to avoid changing these method as
these are used outside mainline module by some OEMs

Flag: EXEMPT bugfix
Bug: 342976579
Test: atest com.android.server.wifi
Change-Id: Ib256f0493d6aa7079cc27ad01e24aa7f8b364fe3
49 files changed