Bug 615834 - get rid of annoying build warning. r+a=merge error

--HG--
extra : rebase_source : f90083159468d4430eeb76787e6f34fd35dfd444

js/src/xpconnect/src/xpcpublic.h

@@ -41,8 +41,10 @@
 #define xpcpublic_h
 
 #include "jsapi.h"
-#include "nsISupports.h"
 #include "jsobj.h"
+#include "jsgc.h"
+
+#include "nsISupports.h"
 #include "nsIPrincipal.h"
 #include "nsWrapperCache.h"