Rollup merge of rust-lang#66820 - dtolnay:fmt3, r=Dylan-DPC

Format libstd with rustfmt

(Same strategy as rust-lang#66691.)

This commit applies rustfmt with rust-lang/rust's default settings to files in src/libstd *that are not involved in any currently open PR* to minimize merge conflicts, and are not part of libstd/os (rust-lang#66818) or libstd/sys (rust-lang#66819). The list of files involved in open PRs was determined by querying GitHub's GraphQL API [with this script](https://gist.github.com/dtolnay/aa9c34993dc051a4f344d1b10e4487e8).

With the list of files from the script in outstanding_files, the relevant commands were:

    $ find src/libstd -name '*.rs' \
        | xargs rustfmt --edition=2018 --unstable-features --skip-children
    $ rg libstd outstanding_files | xargs git checkout --

Repeating this process several months apart should get us coverage of most of the rest of libstd.

To confirm no funny business:

    $ git checkout $THIS_COMMIT^
    $ git show --pretty= --name-only $THIS_COMMIT \
        | xargs rustfmt --edition=2018 --unstable-features --skip-children
    $ git diff $THIS_COMMIT  # there should be no difference

src/libstd/ascii.rs

@@ -17,7 +17,7 @@
 #![stable(feature = "rust1", since = "1.0.0")]
 
 #[stable(feature = "rust1", since = "1.0.0")]
-pub use core::ascii::{EscapeDefault, escape_default};
+pub use core::ascii::{escape_default, EscapeDefault};
 
 /// Extension methods for ASCII-subset only operations.
 ///

src/libstd/backtrace.rs

@@ -95,10 +95,10 @@ use crate::env;
 use crate::fmt;
 use crate::sync::atomic::{AtomicUsize, Ordering::SeqCst};
 use crate::sync::Mutex;
-use crate::sys_common::backtrace::{output_filename, lock};
+use crate::sys_common::backtrace::{lock, output_filename};
 use crate::vec::Vec;
-use backtrace_rs as backtrace;
 use backtrace::BytesOrWideString;
+use backtrace_rs as backtrace;
 
 /// A captured OS thread stack backtrace.
 ///

src/libstd/benches/hash/map.rs

@@ -1,7 +1,7 @@
 #![cfg(test)]
 
-use test::Bencher;
 use std::collections::HashMap;
+use test::Bencher;
 
 #[bench]
 fn new_drop(b: &mut Bencher) {

src/libstd/collections/mod.rs

@@ -413,20 +413,20 @@
 #[doc(hidden)]
 pub use crate::ops::Bound;
 #[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::collections::{BinaryHeap, BTreeMap, BTreeSet};
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::collections::{LinkedList, VecDeque};
-#[stable(feature = "rust1", since = "1.0.0")]
 pub use alloc_crate::collections::{binary_heap, btree_map, btree_set};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use alloc_crate::collections::{linked_list, vec_deque};
+#[stable(feature = "rust1", since = "1.0.0")]
+pub use alloc_crate::collections::{BTreeMap, BTreeSet, BinaryHeap};
+#[stable(feature = "rust1", since = "1.0.0")]
+pub use alloc_crate::collections::{LinkedList, VecDeque};
 
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use self::hash_map::HashMap;
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use self::hash_set::HashSet;
 
-#[unstable(feature = "try_reserve", reason = "new API", issue="48043")]
+#[unstable(feature = "try_reserve", reason = "new API", issue = "48043")]
 pub use alloc_crate::collections::TryReserveError;
 
 mod hash;