arc: Skip GMS Sign-In in case Android is already signed-in.

chrome/browser/chromeos/arc/arc_optin_uma.cc

 // Copyright 2016 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.
 
 #include "chrome/browser/chromeos/arc/arc_optin_uma.h"
 
 #include <string>
 
 #include "base/metrics/histogram_functions.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 46 matching lines @@
   base::UmaHistogramCustomTimes(histogram_name, elapsed_time,
                                 base::TimeDelta::FromSeconds(1) /* minimum */,
                                 base::TimeDelta::FromMinutes(3) /* maximum */,
                                 50 /* bucket_count */);
 }
 
 void UpdateAuthCheckinAttempts(int32_t num_attempts) {
   UMA_HISTOGRAM_SPARSE_SLOWLY("ArcAuth.CheckinAttempts", num_attempts);
 }
 
+void UpdateAuthAccountCheckStatus(AccountCheckStatus status) {
+  UMA_HISTOGRAM_ENUMERATION("ArcAuth.AccountCheckStatus",
+                            static_cast<int>(status),
+                            static_cast<int>(AccountCheckStatus::SIZE));

[dcheng, 2017/03/25 00:55:04]

Hmm... this doesn't work without the static cast?

(Guess not, filed https://crbug.com/705171 for fixing this)

[khmel, 2017/03/25 01:24:14]

Thank for caring this case! I confirmed that this does not compile.

+}
+
 void UpdateSilentAuthCodeUMA(OptInSilentAuthCode state) {
   UMA_HISTOGRAM_ENUMERATION("Arc.OptInSilentAuthCode", static_cast<int>(state),
                             static_cast<int>(OptInSilentAuthCode::SIZE));
 }
 
 std::ostream& operator<<(std::ostream& os, const ProvisioningResult& result) {
 #define MAP_PROVISIONING_RESULT(name) \
   case ProvisioningResult::name:      \
     return os << #name
 
@@ skipping 24 matching lines @@
 
 #undef MAP_PROVISIONING_RESULT
 
   // Some compilers report an error even if all values of an enum-class are
   // covered exhaustively in a switch statement.
   NOTREACHED() << "Invalid value " << static_cast<int>(result);
   return os;
 }
 
 }  // namespace arc