Fix error in tag-that-dare-not-speak-its-name

src/test/ui/tag-that-dare-not-speak-its-name.rs

@@ -1,6 +1,5 @@
 // Issue #876
 
-#![no_implicit_prelude]
 use std::vec::Vec;
 
 fn last<T>(v: Vec<&T> ) -> std::option::Option<T> {

src/test/ui/tag-that-dare-not-speak-its-name.stderr

@@ -1,5 +1,5 @@
 error[E0308]: mismatched types
-  --> $DIR/tag-that-dare-not-speak-its-name.rs:12:20
+  --> $DIR/tag-that-dare-not-speak-its-name.rs:11:20
    |
 LL |     let x : char = last(y);
    |                    ^^^^^^^ expected char, found enum `std::option::Option`