Add an UMA stat to be able to see if the User pods are show on start screen,

chrome/browser/chromeos/login/session/user_session_manager.cc

 // 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.
 
 #include "chrome/browser/chromeos/login/session/user_session_manager.h"
 
 #include <string>
 
 #include "base/base_paths.h"
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/logging.h"
+#include "base/metrics/histogram.h"

[Ilya Sherman, 2015/04/07 21:31:18]

nit: Please include histogram_macros instead

 #include "base/path_service.h"
 #include "base/prefs/pref_member.h"
 #include "base/prefs/pref_registry_simple.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/string16.h"
 #include "base/strings/stringprintf.h"
 #include "base/sys_info.h"
 #include "base/task_runner_util.h"
 #include "base/threading/worker_pool.h"
 #include "chrome/browser/about_flags.h"
@@ skipping 1432 matching lines @@
 
   const user_manager::User* user =
       user_manager::UserManager::Get()->FindUser(user_id);
   EasyUnlockService* easy_unlock_service =
         EasyUnlockService::GetForUser(*user);
   easy_unlock_service->CheckCryptohomeKeysAndMaybeHardlock();
 }
 
 void UserSessionManager::ActiveUserChanged(
     const user_manager::User* active_user) {
+  if (!user_manager::UserManager::Get()->IsCurrentUserNew())
+    SendUserPodsMetrics();
+
   Profile* profile = ProfileHelper::Get()->GetProfileByUser(active_user);
   // If profile has not yet been initialized, delay initialization of IME.
   if (!profile)
     return;
 
   input_method::InputMethodManager* manager =
       input_method::InputMethodManager::Get();
   manager->SetState(
       GetDefaultIMEState(ProfileHelper::Get()->GetProfileByUser(active_user)));
 }
@@ skipping 104 matching lines @@
 void UserSessionManager::RemoveProfileForTesting(Profile* profile) {
   default_ime_states_.erase(profile);
 }
 
 void UserSessionManager::InjectStubUserContext(
     const UserContext& user_context) {
   injected_user_context_.reset(new UserContext(user_context));
   authenticator_ = NULL;
 }
 
+void UserSessionManager::SendUserPodsMetrics() {
+  bool show_users_on_signin;
+  CrosSettings::Get()->GetBoolean(kAccountsPrefShowUserNamesOnSignIn,
+                                  &show_users_on_signin);
+  bool is_enterprise_managed = g_browser_process->platform_part()
+                                   ->browser_policy_connector_chromeos()
+                                   ->IsEnterpriseManaged();
+  UserPodsDisplay display;
+  if (show_users_on_signin) {
+    if (is_enterprise_managed)
+      display = USER_PODS_DISPLAY_ENABLED_MANAGED;
+    else
+      display = USER_PODS_DISPLAY_ENABLED_REGULAR;
+  } else {
+    if (is_enterprise_managed)
+      display = USER_PODS_DISPLAY_DISABLED_MANAGED;
+    else
+      display = USER_PODS_DISPLAY_DISABLED_REGULAR;
+  }
+  UMA_HISTOGRAM_ENUMERATION("UserSessionManager.UserPodsDisplay", display,
+                            NUM_USER_PODS_DISPLAY);
+}
+
 }  // namespace chromeos