Awhile back we explicitly blocked any new ASEC installs, with the
expectation that we'd eventually remove the logic entirely. We've
had them disabled for about a week now without incident, so let's
rip out the remaining code.
Test: bit FrameworksCoreTests:android.content.pm.PackageHelperTests
Test: bit FrameworksCoreTests:android.content.pm.PackageManagerTests
Bug: 32913676
Change-Id: I1ecc35487420731f5c4bdf03bca5751548ce51b3