Add publicAlternatives for setTargetSdkVersion.

Use of this API would allow bypassing of all API greylist enforcement
and invalidates other policies. App should use the official manifest API
instead.

Bug: 136102585
Test: m, inspect out/soong/hiddenapi/hiddenapi-flags.csv
Change-Id: I3d1b88a02e5d28cb6ea47f11ce76f999ba401a15
2 files changed