Classify BinaryHeap & LinkedList unit tests as such

library/alloc/src/collections/binary_heap.rs

@@ -155,6 +155,9 @@ use crate::vec::{self, AsIntoIter, Vec};
 
 use super::SpecExtend;
 
+#[cfg(test)]
+mod tests;
+
 /// A priority queue implemented with a binary heap.
 ///
 /// This will be a max-heap.

library/alloc/tests/binary_heap.rs → library/alloc/src/collections/binary_heap/tests.rs

@@ -1,5 +1,5 @@
-use std::collections::binary_heap::{Drain, PeekMut};
-use std::collections::BinaryHeap;
+use super::*;
+use crate::boxed::Box;
 use std::iter::TrustedLen;
 use std::panic::{catch_unwind, AssertUnwindSafe};
 use std::sync::atomic::{AtomicU32, Ordering};