This removes the requirement to hold the USE_FINGERPRINT permission
to successfully invoke FingerprintManager.getAuthenticatorId().
This is needed because Android Keystore classes which run inside app
processes occasionally need to access this authenticator ID. The
access however is not necessarily triggered by the developer using
APIs to do with fingerprints. Thus, if an app does not hold the
USE_FINGERPRINT permission and uses Android Keystore API, it may
unexpectedly encounter a SecurityException.
It's OK to provide access to authenticator ID without requiring
USE_FINGERPRINT permission because there are other ways to access
this ID without holding that permission, such as though hidden
KeyStore API.
Once Android Keystore code is restructured to no longer require
access to authenticator ID, this CL can be reverted.
Bug: 21030147
Change-Id: I9af29830abce34c46e29e5c1682cc3ab88c95c00