Framework support for AndroidKeyStore migration

- Add a new boolean attribute `inheritKeyStoreKeys` to allow apps to
  indicate whether they want keys to be transferred to the updated app
- Call the appropriate KeyStore method to migrate keys from the old
  namespace to the new one
- Clear keys owned by the previous app ID if it is removed

Test: atest SharedUserMigrationTest#testKeyMigration
Test: atest AndroidPackageTest
Bug: 179284822
Change-Id: I321b85b88c150f17709a2270c0cbaf368ca035cc