diff --git a/common/constants.cc b/common/constants.cc
index 0677e66..ff46755 100644
--- a/common/constants.cc
+++ b/common/constants.cc
@@ -16,133 +16,4 @@
 
 #include "update_engine/common/constants.h"
 
-namespace chromeos_update_engine {
-
-const char kExclusionPrefsSubDir[] = "exclusion";
-
-const char kDlcPrefsSubDir[] = "dlc";
-
-const char kPowerwashSafePrefsSubDirectory[] = "update_engine/prefs";
-
-const char kPrefsSubDirectory[] = "prefs";
-
-const char kStatefulPartition[] = "/mnt/stateful_partition";
-
-const char kPostinstallDefaultScript[] = "postinst";
-
-// Constants defining keys for the persisted state of update engine.
-const char kPrefsAttemptInProgress[] = "attempt-in-progress";
-const char kPrefsBackoffExpiryTime[] = "backoff-expiry-time";
-const char kPrefsBootId[] = "boot-id";
-const char kPrefsCurrentBytesDownloaded[] = "current-bytes-downloaded";
-const char kPrefsCurrentResponseSignature[] = "current-response-signature";
-const char kPrefsCurrentUrlFailureCount[] = "current-url-failure-count";
-const char kPrefsCurrentUrlIndex[] = "current-url-index";
-const char kPrefsDailyMetricsLastReportedAt[] =
-    "daily-metrics-last-reported-at";
-const char kPrefsDeltaUpdateFailures[] = "delta-update-failures";
-const char kPrefsDynamicPartitionMetadataUpdated[] =
-    "dynamic-partition-metadata-updated";
-const char kPrefsFullPayloadAttemptNumber[] = "full-payload-attempt-number";
-const char kPrefsInstallDateDays[] = "install-date-days";
-const char kPrefsLastActivePingDay[] = "last-active-ping-day";
-const char kPrefsLastRollCallPingDay[] = "last-roll-call-ping-day";
-const char kPrefsManifestMetadataSize[] = "manifest-metadata-size";
-const char kPrefsManifestSignatureSize[] = "manifest-signature-size";
-const char kPrefsMetricsAttemptLastReportingTime[] =
-    "metrics-attempt-last-reporting-time";
-const char kPrefsMetricsCheckLastReportingTime[] =
-    "metrics-check-last-reporting-time";
-const char kPrefsNoIgnoreBackoff[] = "no-ignore-backoff";
-const char kPrefsNumReboots[] = "num-reboots";
-const char kPrefsNumResponsesSeen[] = "num-responses-seen";
-const char kPrefsOmahaCohort[] = "omaha-cohort";
-const char kPrefsOmahaCohortHint[] = "omaha-cohort-hint";
-const char kPrefsOmahaCohortName[] = "omaha-cohort-name";
-const char kPrefsOmahaEolDate[] = "omaha-eol-date";
-const char kPrefsP2PEnabled[] = "p2p-enabled";
-const char kPrefsP2PFirstAttemptTimestamp[] = "p2p-first-attempt-timestamp";
-const char kPrefsP2PNumAttempts[] = "p2p-num-attempts";
-const char kPrefsPayloadAttemptNumber[] = "payload-attempt-number";
-const char kPrefsTestUpdateCheckIntervalTimeout[] =
-    "test-update-check-interval-timeout";
-// Keep |kPrefsPingActive| in sync with |kDlcMetadataFilePingActive| in
-// dlcservice.
-const char kPrefsPingActive[] = "active";
-const char kPrefsPingLastActive[] = "date_last_active";
-const char kPrefsPingLastRollcall[] = "date_last_rollcall";
-const char kPrefsLastFp[] = "last-fp";
-const char kPrefsPostInstallSucceeded[] = "post-install-succeeded";
-const char kPrefsPreviousVersion[] = "previous-version";
-const char kPrefsResumedUpdateFailures[] = "resumed-update-failures";
-const char kPrefsRollbackHappened[] = "rollback-happened";
-const char kPrefsRollbackVersion[] = "rollback-version";
-const char kPrefsChannelOnSlotPrefix[] = "channel-on-slot-";
-const char kPrefsSystemUpdatedMarker[] = "system-updated-marker";
-const char kPrefsTargetVersionAttempt[] = "target-version-attempt";
-const char kPrefsTargetVersionInstalledFrom[] = "target-version-installed-from";
-const char kPrefsTargetVersionUniqueId[] = "target-version-unique-id";
-const char kPrefsTotalBytesDownloaded[] = "total-bytes-downloaded";
-const char kPrefsUpdateCheckCount[] = "update-check-count";
-const char kPrefsUpdateCheckResponseHash[] = "update-check-response-hash";
-const char kPrefsUpdateCompletedBootTime[] = "update-completed-boot-time";
-const char kPrefsUpdateCompletedOnBootId[] = "update-completed-on-boot-id";
-const char kPrefsUpdateDurationUptime[] = "update-duration-uptime";
-const char kPrefsUpdateFirstSeenAt[] = "update-first-seen-at";
-const char kPrefsUpdateOverCellularPermission[] =
-    "update-over-cellular-permission";
-const char kPrefsUpdateOverCellularTargetVersion[] =
-    "update-over-cellular-target-version";
-const char kPrefsUpdateOverCellularTargetSize[] =
-    "update-over-cellular-target-size";
-const char kPrefsUpdateServerCertificate[] = "update-server-cert";
-const char kPrefsUpdateStateNextDataLength[] = "update-state-next-data-length";
-const char kPrefsUpdateStateNextDataOffset[] = "update-state-next-data-offset";
-const char kPrefsUpdateStateNextOperation[] = "update-state-next-operation";
-const char kPrefsUpdateStatePayloadIndex[] = "update-state-payload-index";
-const char kPrefsUpdateStateSHA256Context[] = "update-state-sha-256-context";
-const char kPrefsUpdateStateSignatureBlob[] = "update-state-signature-blob";
-const char kPrefsUpdateStateSignedSHA256Context[] =
-    "update-state-signed-sha-256-context";
-const char kPrefsUpdateBootTimestampStart[] = "update-boot-timestamp-start";
-const char kPrefsUpdateTimestampStart[] = "update-timestamp-start";
-const char kPrefsUrlSwitchCount[] = "url-switch-count";
-const char kPrefsVerityWritten[] = "verity-written";
-const char kPrefsWallClockScatteringWaitPeriod[] = "wall-clock-wait-period";
-const char kPrefsWallClockStagingWaitPeriod[] =
-    "wall-clock-staging-wait-period";
-const char kPrefsManifestBytes[] = "manifest-bytes";
-const char kPrefsPreviousSlot[] = "previous-slot";
-
-// These four fields are generated by scripts/brillo_update_payload.
-const char kPayloadPropertyFileSize[] = "FILE_SIZE";
-const char kPayloadPropertyFileHash[] = "FILE_HASH";
-const char kPayloadPropertyMetadataSize[] = "METADATA_SIZE";
-const char kPayloadPropertyMetadataHash[] = "METADATA_HASH";
-// The Authorization: HTTP header to be sent when downloading the payload.
-const char kPayloadPropertyAuthorization[] = "AUTHORIZATION";
-// The User-Agent HTTP header to be sent when downloading the payload.
-const char kPayloadPropertyUserAgent[] = "USER_AGENT";
-// Set "POWERWASH=1" to powerwash (factory data reset) the device after
-// applying the update.
-const char kPayloadPropertyPowerwash[] = "POWERWASH";
-// The network id to pass to android_setprocnetwork before downloading.
-// This can be used to zero-rate OTA traffic by sending it over the correct
-// network.
-const char kPayloadPropertyNetworkId[] = "NETWORK_ID";
-// Set "SWITCH_SLOT_ON_REBOOT=0" to skip marking the updated partitions active.
-// The default is 1 (always switch slot if update succeeded).
-const char kPayloadPropertySwitchSlotOnReboot[] = "SWITCH_SLOT_ON_REBOOT";
-// Set "RUN_POST_INSTALL=0" to skip running optional post install.
-// The default is 1 (always run post install).
-const char kPayloadPropertyRunPostInstall[] = "RUN_POST_INSTALL";
-
-const char kOmahaUpdaterVersion[] = "0.1.0.0";
-
-// X-Goog-Update headers.
-const char kXGoogleUpdateInteractivity[] = "X-Goog-Update-Interactivity";
-const char kXGoogleUpdateAppId[] = "X-Goog-Update-AppId";
-const char kXGoogleUpdateUpdater[] = "X-Goog-Update-Updater";
-const char kXGoogleUpdateSessionId[] = "X-Goog-SessionId";
-
-}  // namespace chromeos_update_engine
+namespace chromeos_update_engine {}  // namespace chromeos_update_engine