diff --git a/services/sync/tests/unit/head_first.js b/services/sync/tests/unit/head_first.js
index 7864ba09d6e..ba4895471d4 100644
--- a/services/sync/tests/unit/head_first.js
+++ b/services/sync/tests/unit/head_first.js
@@ -260,3 +260,11 @@ function FakeFilesystemService(contents) {
     return [fakeStream];
   };
 };
+
+function FakeGUIDService() {
+  let latestGUID = 0;
+
+  Utils.makeGUID = function fake_makeGUID() {
+    return "fake-guid-" + latestGUID++;
+  };
+}
diff --git a/services/sync/tests/unit/test_passwords.js b/services/sync/tests/unit/test_passwords.js
index be9e9b4f21e..9deddd6b30d 100644
--- a/services/sync/tests/unit/test_passwords.js
+++ b/services/sync/tests/unit/test_passwords.js
@@ -116,14 +116,6 @@ var ffs = new FakeFilesystemService({});
 var fgs = new FakeGUIDService();
 var fakeLoginManager = new FakeLoginManager(__fakeLogins);
 
-function FakeGUIDService() {
-  let latestGUID = 0;
-
-  Utils.makeGUID = function fake_makeGUID() {
-    return "fake-guid-" + latestGUID++;
-  };
-}
-
 function FakeLoginManager(fakeLogins) {
   this.fakeLogins = fakeLogins;