cros: Add enterprise user session metrics

chrome/common/pref_names.cc

 // Copyright (c) 2012 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/common/pref_names.h"
 
 #include "base/macros.h"
 #include "build/build_config.h"
 #include "chrome/common/features.h"
 #include "chrome/common/pref_font_webkit_names.h"
@@ skipping 713 matching lines @@
 // user is logged out when the maximum session time is reached. The user is
 // informed about the remaining time by a countdown timer shown in the ash
 // system tray.
 const char kSessionLengthLimit[] = "session.length_limit";
 
 // Whether the session length limit should start running only after the first
 // user activity has been observed in a session.
 const char kSessionWaitForInitialUserActivity[] =
     "session.wait_for_initial_user_activity";
 
+// A preference of the last user session type. It is used with the
+// kLastSessionLength pref below to store the last user session info
+// on shutdown so that it could be reported on the next run.
+const char kLastSessionType[] = "session.last_session_type";
+
+// A preference of the last user session length.
+const char kLastSessionLength[] = "session.last_session_length";
+
 // Inactivity time in milliseconds while the system is on AC power before
 // the screen should be dimmed, turned off, or locked, before an
 // IdleActionImminent D-Bus signal should be sent, or before
 // kPowerAcIdleAction should be performed.  0 disables the delay (N/A for
 // kPowerAcIdleDelayMs).
 const char kPowerAcScreenDimDelayMs[] = "power.ac_screen_dim_delay_ms";
 const char kPowerAcScreenOffDelayMs[] = "power.ac_screen_off_delay_ms";
 const char kPowerAcScreenLockDelayMs[] = "power.ac_screen_lock_delay_ms";
 const char kPowerAcIdleWarningDelayMs[] = "power.ac_idle_warning_delay_ms";
 const char kPowerAcIdleDelayMs[] = "power.ac_idle_delay_ms";
@@ skipping 1696 matching lines @@
 
 // Number of times user has seen the "desktop to iOS" history page promotion.
 const char kNumberHistoryPageIOSPromoShown[] =
     "history_page_ios_promo_shown_count";
 
 // True if the user has dismissed the "desktop to iOS" history page promotion.
 const char kHistoryPageIOSPromoDismissed[] = "history_page_ios_promo_dismissed";
 #endif
 
 }  // namespace prefs