Revert removed #![feature(nll)]

taiki-e · taiki-e · commit e40eab0e8ae9 · 2019-02-10T16:13:30.000+09:00
[git filter-repo] original commit: rust-lang/rust@2be0993
diff --git a/lib.rs b/lib.rs
@@ -34,6 +34,7 @@
 #![forbid(unsafe_code)]
 #![deny(rust_2018_idioms)]
 
+#![feature(nll)]
 #![feature(try_from)]
 // See librustc_cratesio_shim/Cargo.toml for a comment explaining this.
 #[allow(unused_extern_crates)]
