Revoke storage on SDK downgrade or new full storage request

When an app downgrades from above API 28 to below, or when an app begins
requesting full storage in api 29, revoke storage permissions

Test: Atest StorageEscalationTest
Bug: 171430330
Change-Id: Ia6bd5658b77a26ab15fea013ec875050457473e0
1 file changed