Persist setup metrics and have Chrome report them during UMA upload.

components/metrics/metrics_state_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 "components/metrics/metrics_state_manager.h"
 
 #include "base/command_line.h"
 #include "base/guid.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/metrics/sparse_histogram.h"
@@ skipping 182 matching lines @@
   return result.Pass();
 }
 
 // static
 void MetricsStateManager::RegisterPrefs(PrefRegistrySimple* registry) {
   registry->RegisterBooleanPref(prefs::kMetricsResetIds, false);
   registry->RegisterStringPref(prefs::kMetricsClientID, std::string());
   registry->RegisterInt64Pref(prefs::kMetricsReportingEnabledTimestamp, 0);
   registry->RegisterIntegerPref(prefs::kMetricsLowEntropySource,
                                 kLowEntropySourceNotSet);
+  registry->RegisterInt64Pref(prefs::kSetupMetricsLastSeen, 0);
 
   ClonedInstallDetector::RegisterPrefs(registry);
   CachingPermutedEntropyProvider::RegisterPrefs(registry);
 }
 
 void MetricsStateManager::BackUpCurrentClientInfo() {
   ClientInfo client_info;
   client_info.client_id = client_id_;
   client_info.installation_date = local_state_->GetInt64(prefs::kInstallDate);
   client_info.reporting_enabled_date =
@@ skipping 87 matching lines @@
 
   local_state_->ClearPref(prefs::kMetricsClientID);
   local_state_->ClearPref(prefs::kMetricsLowEntropySource);
   local_state_->ClearPref(prefs::kMetricsResetIds);
 
   // Also clear the backed up client info.
   store_client_info_.Run(ClientInfo());
 }
 
 }  // namespace metrics