Record policy usage statistics every 24 hours.

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/basictypes.h"
 
 namespace prefs {
 
@@ skipping 2018 matching lines @@
 const char kInManagedMode[] = "managed_mode";
 
 // Counts how many more times the 'profile on a network share' warning should be
 // shown to the user before the next silence period.
 const char kNetworkProfileWarningsLeft[] = "network_profile.warnings_left";
 // Tracks the time of the last shown warning. Used to reset
 // |network_profile.warnings_left| after a silence period.
 const char kNetworkProfileLastWarningTime[] =
     "network_profile.last_warning_time";
 
+// 64-bit serialization of the time last policy usage statistics were collected
+// by UMA_HISTOGRAM_ENUMERATION.
+const char kLastPolicyStatisticsUpdate[] = "policy.last_statistics_update";
+
 }  // namespace prefs