cros: Add PinStorageProvider enum which describes pin backend in use.

chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.h

Index: chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.h
diff --git a/chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.h b/chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.h
index 8508fe469e882614532f3b1ea71591f5f3f8e9ff..7c01d00565f292ec25f4113d2985147753f0de16 100644
--- a/chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.h
+++ b/chrome/browser/chromeos/login/quick_unlock/quick_unlock_utils.h
@@ -36,11 +36,17 @@ void RegisterProfilePrefs(PrefRegistrySimple* registry);
 // flag is present.
 bool IsPinEnabled(PrefService* pref_service);
 
+// What subsystem should provide pin storage and authentication?
+enum class PinStorageProvider { Prefs, Cryptohome };

[achuithb, 2017/04/17 22:04:12]

newline after this line.

Is there a better name? PinStorageProvider sounds like a class, not an enum.

Shouldn't the values be kPrefs, kCryptohome?

+// Returns the pin storage provider that should be used. IsPinEnabled() must
+// return true for this result to be valid.
+PinStorageProvider GetPinStorageProvider();
+
 // Returns true if the fingerprint unlock feature flag is present.
 bool IsFingerprintEnabled();
 
-// Forcibly enable quick-unlock for testing.
-void EnableForTesting();
+// Forcibly enable all quick-unlock modes for testing.
+void EnableForTesting(PinStorageProvider pin_storage_provider);
 
 }  // namespace quick_unlock
 }  // namespace chromeos