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

components/metrics/metrics_pref_names.cc

Index: components/metrics/metrics_pref_names.cc
diff --git a/components/metrics/metrics_pref_names.cc b/components/metrics/metrics_pref_names.cc
index 8b96e1a1aac0633f8ea0c29da18be3f8f265f9ab..17b6c01c97da37ab3e7f88b01717cb32f992adc3 100644
--- a/components/metrics/metrics_pref_names.cc
+++ b/components/metrics/metrics_pref_names.cc
@@ -7,6 +7,10 @@
 namespace metrics {
 namespace prefs {
 
+// Set once, to the current epoch time, on the first run of chrome on this
+// machine. Attached to metrics reports forever thereafter.
+const char kInstallDate[] = "uninstall_metrics.installation_date2";
+
 // The metrics client GUID.
 // Note: The name client_id2 is a result of creating
 // new prefs to do a one-time reset of the previous values.