UMA for pin unlock success/failure.

chrome/browser/chromeos/login/lock/screen_locker.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_CHROMEOS_LOGIN_LOCK_SCREEN_LOCKER_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_LOCK_SCREEN_LOCKER_H_
 
 #include <memory>
 #include <string>
 
@@ skipping 113 matching lines @@
   // Returns the tester
   static test::ScreenLockerTester* GetTester();
 
  private:
   friend class base::DeleteHelper<ScreenLocker>;
   friend class test::ScreenLockerTester;
   friend class test::ScreenLockerViewsTester;
   friend class test::WebUIScreenLockerTester;
   friend class ScreenLockerDelegate;
 
+  enum UnlockType { AUTH_PASSWORD = 0, AUTH_PIN, AUTH_COUNT };

[jdufault, 2016/08/18 17:48:50]

There's a semi-standard comment block that is put on enums used in UMA warning
readers not to modify order/etc. Can you add it here as well?

+
   struct AuthenticationParametersCapture {
     UserContext user_context;
   };
 
   ~ScreenLocker() override;
 
   // Sets the authenticator.
   void SetAuthenticator(Authenticator* authenticator);
 
   // Called when the screen lock is ready.
@@ skipping 16 matching lines @@
 
   // Used to authenticate the user to unlock.
   scoped_refptr<Authenticator> authenticator_;
 
   // Used to authenticate the user to unlock supervised users.
   scoped_refptr<ExtendedAuthenticator> extended_authenticator_;
 
   // True if the screen is locked, or false otherwise.  This changes
   // from false to true, but will never change from true to
   // false. Instead, ScreenLocker object gets deleted when unlocked.
-  bool locked_;
+  bool locked_ = false;
 
   // Reference to the single instance of the screen locker object.
   // This is used to make sure there is only one screen locker instance.
   static ScreenLocker* screen_locker_;
 
   // The time when the screen locker object is created.
-  base::Time start_time_;
+  base::Time start_time_ = base::Time::Now();
   // The time when the authentication is started.
   base::Time authentication_start_time_;
 
   // Delegate to forward all login status events to.
   // Tests can use this to receive login status events.
-  AuthStatusConsumer* auth_status_consumer_;
+  AuthStatusConsumer* auth_status_consumer_ = nullptr;
 
   // Number of bad login attempts in a row.
-  int incorrect_passwords_count_;
+  int incorrect_passwords_count_ = 0;
+
+  // Whether the last password entered was a pin or not.
+  bool is_pin_attempt_ = false;
 
   // Copy of parameters passed to last call of OnLoginSuccess for usage in
   // UnlockOnLoginSuccess().
   std::unique_ptr<AuthenticationParametersCapture> authentication_capture_;
 
   // Provider for button icon set by the screenlockPrivate API.
   std::unique_ptr<ScreenlockIconProvider> screenlock_icon_provider_;
 
   scoped_refptr<input_method::InputMethodManager::State> saved_ime_state_;
 
   base::WeakPtrFactory<ScreenLocker> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(ScreenLocker);
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_LOCK_SCREEN_LOCKER_H_