Bustage fix.

widget/src/mac/nsDragHelperService.cpp

@@ -38,10 +38,10 @@
 #include "nsDragHelperService.h"
 
 #include "nsGUIEvent.h"
+#include "nsIDOMNode.h"
 #include "nsIDragSessionMac.h"
 #include "nsIServiceManager.h"
 
-
 #define kDragServiceContractID "@mozilla.org/widget/dragservice;1"