Revert "Rollup merge of #67727 - Dylan-DPC:stabilise/remove_item, r=alexcrichton"

This reverts commit 4ed415b, reversing
changes made to 3cce950.

Author: tesuji

src/liballoc/tests/lib.rs

@@ -11,6 +11,7 @@
 #![feature(associated_type_bounds)]
 #![feature(binary_heap_into_iter_sorted)]
 #![feature(binary_heap_drain_sorted)]
+#![feature(vec_remove_item)]
 
 use std::collections::hash_map::DefaultHasher;
 use std::hash::{Hash, Hasher};

src/liballoc/vec.rs

@@ -1696,13 +1696,14 @@ impl<T> Vec<T> {
     /// # Examples
     ///
     /// ```
+    /// # #![feature(vec_remove_item)]
     /// let mut vec = vec![1, 2, 3, 1];
     ///
     /// vec.remove_item(&1);
     ///
     /// assert_eq!(vec, vec![2, 3, 1]);
     /// ```
-    #[stable(feature = "vec_remove_item", since = "1.42.0")]
+    #[unstable(feature = "vec_remove_item", reason = "recently added", issue = "40062")]
     pub fn remove_item<V>(&mut self, item: &V) -> Option<T>
     where
         T: PartialEq<V>,

src/librustc/lib.rs

@@ -50,6 +50,7 @@
 #![feature(thread_local)]
 #![feature(trace_macros)]
 #![feature(trusted_len)]
+#![feature(vec_remove_item)]
 #![feature(stmt_expr_attributes)]
 #![feature(integer_atomics)]
 #![feature(test)]

src/librustdoc/lib.rs

@@ -10,6 +10,7 @@
 #![feature(nll)]
 #![feature(set_stdio)]
 #![feature(test)]
+#![feature(vec_remove_item)]
 #![feature(ptr_offset_from)]
 #![feature(crate_visibility_modifier)]
 #![feature(const_fn)]

src/tools/compiletest/src/main.rs

@@ -1,4 +1,5 @@
 #![crate_name = "compiletest"]
+#![feature(vec_remove_item)]
 #![deny(warnings)]
 // The `test` crate is the only unstable feature
 // allowed here, just to share similar code.