Added UMA stat to track migration of profile_ever_initialized attribute.

components/user_manager/known_user.cc

 // Copyright 2015 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 "components/user_manager/known_user.h"
 
 #include <stddef.h>
 
 #include <memory>
 #include <utility>
 
 #include "base/logging.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/values.h"
 #include "components/prefs/pref_registry_simple.h"
 #include "components/prefs/scoped_user_pref_update.h"
 #include "components/user_manager/user_manager.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 
 namespace user_manager {
 namespace known_user {
 namespace {
 
@@ skipping 426 matching lines @@
 
 bool IsUsingSAML(const AccountId& account_id) {
   bool using_saml;
   if (GetBooleanPref(account_id, kUsingSAMLKey, &using_saml))
     return using_saml;
   return false;
 }
 
 bool WasProfileEverInitialized(const AccountId& account_id) {
   bool profile_ever_initialized;
-  if (GetBooleanPref(account_id, kProfileEverInitialized,
-                     &profile_ever_initialized))
+  const bool pref_set = GetBooleanPref(account_id, kProfileEverInitialized,
+                                       &profile_ever_initialized);
+  // TODO(atwilson): Remove migration code below once this UMA stat reports
+  // that migration is completed - crbug.com/736760.
+  UMA_HISTOGRAM_BOOLEAN("UserManager.ProfileEverInitializedMigrationCompleted",
+                        pref_set);
+  if (pref_set)
     return profile_ever_initialized;
 
   // Sessions created before we started setting the session_initialized flag
   // should default to "initialized = true".
   LOG(WARNING) << "Treating unmigrated user as profile_ever_initialized=true";
   return true;
 }
 
 void SetProfileEverInitialized(const AccountId& account_id, bool initialized) {
   SetBooleanPref(account_id, kProfileEverInitialized, initialized);
@@ skipping 30 matching lines @@
 void RemovePrefsForTesting(const AccountId& account_id) {
   RemovePrefs(account_id);
 }
 
 void RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterListPref(kKnownUsers);
 }
 
 }  // namespace known_user
 }  // namespace user_manager