diff --git a/dom/quota/moz.build b/dom/quota/moz.build
index 2e88d564f76..94dc67cdd0b 100644
--- a/dom/quota/moz.build
+++ b/dom/quota/moz.build
@@ -31,7 +31,7 @@ EXPORTS.mozilla.dom.quota += [
     'Utilities.h',
 ]
 
-SOURCES += [
+UNIFIED_SOURCES += [
     'CheckQuotaHelper.cpp',
     'FileStreams.cpp',
     'QuotaManager.cpp',