SignChallengeCallback 366 chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.cc void EPKPChallengeMachineKey::SignChallengeCallback( SignChallengeCallback 513 chrome/browser/extensions/api/enterprise_platform_keys_private/enterprise_platform_keys_private_api.cc void EPKPChallengeUserKey::SignChallengeCallback(bool register_key,