Log UMA metrics for multiprofile actions.

chrome/browser/chromeos/login/user_manager_impl.cc

Index: chrome/browser/chromeos/login/user_manager_impl.cc
diff --git a/chrome/browser/chromeos/login/user_manager_impl.cc b/chrome/browser/chromeos/login/user_manager_impl.cc
index 9e20d44897a41a88a65549b9d90602a3c401e7d9..d07e01da34326eea6dada13ba1d2cf381c1bb7ed 100644
--- a/chrome/browser/chromeos/login/user_manager_impl.cc
+++ b/chrome/browser/chromeos/login/user_manager_impl.cc
@@ -401,14 +401,20 @@ void UserManagerImpl::UserLoggedIn(const std::string& email,
   logged_in_users_.insert(logged_in_users_.begin(), active_user_);
   SetLRUUser(active_user_);
 
-  if (!primary_user_)
+  if (!primary_user_) {
     primary_user_ = active_user_;
+    if (primary_user_->GetType() == User::USER_TYPE_REGULAR)
+      SendRegularUserLoginMetrics(email);
+  }
 
   UMA_HISTOGRAM_ENUMERATION("UserManager.LoginUserType",
                             active_user_->GetType(), User::NUM_USER_TYPES);
 
-  if (active_user_->GetType() == User::USER_TYPE_REGULAR)
-    SendRegularUserLoginMetrics(email);
+  if (IsMultipleProfilesAllowed()) {
+    UMA_HISTOGRAM_COUNTS_100("MultiProfile.UserCount",
+                             GetUsersAdmittedForMultiProfile().size());

[oshima, 2013/09/28 11:45:19]

shouldn't this be in MultiProfileUMA too?

[xiyuan, 2013/09/28 14:50:26]

GetUsersAdmittedForMultiProfile() returns the users that are allowed to sign
into the current session. Just checked the histograms.xml, it seems
MultiProfile.UserCount wants the # of users in the current session. In this
case, we should use GetLoggedInUsers() here.

[Tim Song, 2013/09/30 17:19:39]

Very nice catch Xiyuan. I misunderstood what GetUsersAdmittedForMultiProfile()
did, and GetLoggedInUsers() is what we want.

It also seems odd to put this in an ash/ file as this isn't really a UI metric.

+  }
+
   g_browser_process->local_state()->SetString(kLastLoggedInRegularUser,
     (active_user_->GetType() == User::USER_TYPE_REGULAR) ? email : "");