arc: Handle metrics for Auth operations.

chrome/browser/chromeos/arc/arc_optin_uma.h

Index: chrome/browser/chromeos/arc/arc_optin_uma.h
diff --git a/chrome/browser/chromeos/arc/arc_optin_uma.h b/chrome/browser/chromeos/arc/arc_optin_uma.h
index d73764406e6c8f2a51aa0a36100031c1a5433ec2..d78946c085e3212eeaf69bb93dd2048e8a72e5e8 100644
--- a/chrome/browser/chromeos/arc/arc_optin_uma.h
+++ b/chrome/browser/chromeos/arc/arc_optin_uma.h
@@ -6,6 +6,7 @@
 #define CHROME_BROWSER_CHROMEOS_ARC_ARC_OPTIN_UMA_H_
 
 #include <ostream>
+#include <string>
 
 namespace base {
 class TimeDelta;
@@ -121,6 +122,9 @@ void UpdateProvisioningTiming(const base::TimeDelta& elapsed_time,
                               bool success,
                               bool managed);
 void UpdateSilentAuthCodeUMA(OptInSilentAuthCode state);
+void UpdateAuthTiming(const std::string& key,
+                      const base::TimeDelta& elapsed_time);
+void UpdateAuthAttempts(const std::string& key, int32_t value);
 
 // Outputs the stringified |result| to |os|. This is only for logging purposes.
 std::ostream& operator<<(std::ostream& os, const ProvisioningResult& result);