cros: Added policies for screen unlock.

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

Index: chrome/browser/chromeos/login/quick_unlock/pin_storage.h
diff --git a/chrome/browser/chromeos/login/quick_unlock/pin_storage.h b/chrome/browser/chromeos/login/quick_unlock/pin_storage.h
index f9fe72aadbecff1921e3716e0c1d82bf26680110..ba047347dc6fb38de3476b284db4abcf609b6a92 100644
--- a/chrome/browser/chromeos/login/quick_unlock/pin_storage.h
+++ b/chrome/browser/chromeos/login/quick_unlock/pin_storage.h
@@ -25,7 +25,6 @@ class PinStorage : public KeyedService {
  public:
   // TODO(jdufault): Pull these values in from policy. See crbug.com/612271.
   static const int kMaximumUnlockAttempts = 3;

[jdufault, 2016/10/04 17:55:06]

This value should be changeable using policy.

[sammiequon, 2016/10/18 22:47:49]

I did not see this on the doc, but I will do it in a separate CL.

-  static const base::TimeDelta kStrongAuthTimeout;
 
   // Registers profile prefs.
   static void RegisterProfilePrefs(user_prefs::PrefRegistrySyncable* registry);
@@ -39,6 +38,9 @@ class PinStorage : public KeyedService {
   void MarkStrongAuth();
   // Returns true if the user has been strongly authenticated.
   bool HasStrongAuth() const;

[jdufault, 2016/10/04 17:55:06]

Why did you decide to define NeedsStrongAuth separately from HasStrongAuth? It
seems reasonable to put all of the NeedsStrongAuth logic into HasStrongAuth.

Right now, it is very confusing for a reader because HasStrongAuth and
NeedsStrongAuth are only subtly different. This makes the API confusing.

[sammiequon, 2016/10/18 22:47:49]

I thought HasStrongAuth would be needed separately on some cases. A lot tests
check to see if last_strong_auth is null.

[jdufault, 2016/10/21 19:03:44]

The API is very confusing right now, I think it's worth adding such a method to
a test utility class instead of here.

FWIW, it should generally not be possible to have a PinStorage instance where
there is no last_strong_auth_ time.

[sammiequon, 2016/10/21 23:49:24]

Done.

+  // Returns true if the user last strong authentication was longer than the set
+  // preference. This should not be called if HasStrongAuth returns false.
+  bool NeedsStrongAuth() const;
   // Returns the time since the last strong authentication. This should not be
   // called if HasStrongAuth returns false.
   base::TimeDelta TimeSinceLastStrongAuth() const;
@@ -56,6 +58,8 @@ class PinStorage : public KeyedService {
   void SetPin(const std::string& pin);
   // Removes the pin; IsPinSet will return false.
   void RemovePin();
+  // Checks the to see if pin unlock enabled.
+  bool IsPinUnlockEnabled() const;
 
   // Is PIN entry currently available?
   bool IsPinAuthenticationAvailable() const;