servo: Merge #14889 - Upgrade to rustc 1.16.0-nightly (6f1ae663e 2017-01-06) (from servo:rustup); r=jdm

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Source-Repo: https://github.com/servo/servo
Source-Revision: df895cb80c460594f220b6cf28aa5869464d05ec

servo/components/script_traits/lib.rs

@@ -6,7 +6,7 @@
 //! The traits are here instead of in script so that these modules won't have
 //! to depend on script.
 
-#![feature(plugin, proc_macro)]
+#![feature(plugin)]
 #![plugin(plugins)]
 #![deny(missing_docs)]
 #![deny(unsafe_code)]