Switch RecoverySystem impl to use sun.security.pkcs

Due to org.apache.harmony.security package removal,
RecoverySystem#verifyPackage was rewritten to use
sun.security.pkcs package for verifining package
signature.

(cherry-picked from 84acbd76f7e1300e8404ac1b94f008826f9cc0fb)

Change-Id: I3a2058982beadab1aaae793c25db5c6f7387a72b
1 file changed