Remove Android compat annotations on jarjar transform.

Set a system property to enable Android specific transformer that drops
UnsupportedAppUsage annotation for repackaged classes to avoid adding
unneeded hidden api symbols on jarjar.

Bug: 146418363
Test: m, manual diff hiddenapi-flags.csv
Exempt-From-Owner-Approval: patch approved by owner
Change-Id: I10b49feb15257301574162b5d389cbc30277f672
Merged-In: I10b49feb15257301574162b5d389cbc30277f672
(cherry picked from commit 762d9f38)