Move kInstallDate from chrome/common/pref_names.h to components/metrics/metrics_pref_names.h

components/metrics/metrics_service.cc

Index: components/metrics/metrics_service.cc
diff --git a/components/metrics/metrics_service.cc b/components/metrics/metrics_service.cc
index 66ee1ced355ca87a5638100942f153592ad07ff1..2df2bf5660b982d533be6e71973b9fcbe80ece13 100644
--- a/components/metrics/metrics_service.cc
+++ b/components/metrics/metrics_service.cc
@@ -383,6 +383,10 @@ std::string MetricsService::GetClientId() {
   return state_manager_->client_id();
 }
 
+int64 MetricsService::GetInstallDate() {
+  return client_->GetInstallDate();
+}
+
 scoped_ptr<const base::FieldTrial::EntropyProvider>
 MetricsService::CreateEntropyProvider() {
   // TODO(asvitkine): Refactor the code so that MetricsService does not expose