Add @UnsupportedAppUsage annotations

For packages:
  android.accounts
  android.app

This is an automatically generated CL. See go/UnsupportedAppUsage
for more details.

Exempted-From-Owner-Approval: Mechanical changes to the codebase
which have been approved by Android API council and announced on
android-eng@

Bug: 110868826
Test: m
Merged-In: I65c961e3f59b9868156b3ee6a3b1cab81b0e9d25
Change-Id: I47b5f45ced1c6e385ed24424e442c76fc0487af7