fixing WIN32 bustage

xpcom/build/dlldeps.cpp

@@ -89,8 +89,7 @@
 #include "nsEscape.h"
 #include "nsStreamUtils.h"
 
-#define nsAString_external nsAString_external_
-#define nsACString_external nsACString_external_
+#define NS_STRINGAPI_IMPL
 #include "nsStringAPI.h"
 
 void XXXNeverCalled()