Changing the UsersPerSession UMA metric to only count possible multi profile sessions and do this u…

ash/multi_profile_uma.h

 // Copyright 2013 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.
 
 #ifndef ASH_MULTI_PROFILE_UMA_H_
 #define ASH_MULTI_PROFILE_UMA_H_
 
 #include "ash/ash_export.h"
 #include "base/basictypes.h"
 
@@ skipping 51 matching lines @@
 
   // Record switching the active user and what UI path was taken.
   static void RecordSwitchActiveUser(SwitchActiveUserAction action);
 
   // Record the type of window which got teleported to another desk.
   static void RecordTeleportWindowType(TeleportWindowType window_type);
 
   // Record the way and how many times a window got teleported to another desk.
   static void RecordTeleportAction(TeleportWindowAction action);
 
-  // Record number of users joined into a session. Called upon logout.
+  // Record number of users joined into a session. Called every time a user gets
+  // added.
   static void RecordUserCount(int number_of_users);
 
   // Record a discarded tab in the number of running users bucket.
   static void RecordDiscardedTab(int number_of_users);
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(MultiProfileUMA);
 };
 
 }  // namespace ash
 
 #endif  // ASH_MULTI_PROFILE_UMA_H_