diff --git a/common/constants.h b/common/constants.h
index 3685102..1e97249 100644
--- a/common/constants.h
+++ b/common/constants.h
@@ -71,6 +71,7 @@
 extern const char kPrefsPingActive[];
 extern const char kPrefsPingLastActive[];
 extern const char kPrefsPingLastRollcall[];
+extern const char kPrefsLastFp[];
 extern const char kPrefsPostInstallSucceeded[];
 extern const char kPrefsPreviousVersion[];
 extern const char kPrefsResumedUpdateFailures[];