diff --git a/common/constants.h b/common/constants.h
index 78353d8..d97c5fb 100644
--- a/common/constants.h
+++ b/common/constants.h
@@ -90,7 +90,8 @@
 extern const char kPrefsUpdateStateSignedSHA256Context[];
 extern const char kPrefsUpdateTimestampStart[];
 extern const char kPrefsUrlSwitchCount[];
-extern const char kPrefsWallClockWaitPeriod[];
+extern const char kPrefsWallClockScatteringWaitPeriod[];
+extern const char kPrefsWallClockStagingWaitPeriod[];
 
 // Keys used when storing and loading payload properties.
 extern const char kPayloadPropertyFileSize[];