Auto merge of #19083 - servo:vis, r=SimonSapin

Fix new failure in Nightly 2017-11-01.

The rustc::declare_lints! macro started using a :vis fragment specifier.

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components/script_plugins/lib.rs

@@ -15,6 +15,7 @@
 
 
 #![deny(unsafe_code)]
+#![feature(macro_vis_matcher)]
 #![feature(plugin)]
 #![feature(plugin_registrar)]
 #![feature(rustc_private)]