Format libstd with rustfmt

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. 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

1 files changed, 6 insertions, 8 deletions

diff --git a/src/libstd/sys_common/fs.rs b/src/libstd/sys_common/fs.rs
index 7152fcd215c..e30e8018a31 100644
--- a/src/libstd/sys_common/fs.rs
+++ b/src/libstd/sys_common/fs.rs
@@ -1,13 +1,15 @@
 #![allow(dead_code)] // not used on all platforms
 
-use crate::path::Path;
 use crate::fs;
 use crate::io::{self, Error, ErrorKind};
+use crate::path::Path;
 
 pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
     if !from.is_file() {
-        return Err(Error::new(ErrorKind::InvalidInput,
-                              "the source path is not an existing regular file"))
+        return Err(Error::new(
+            ErrorKind::InvalidInput,
+            "the source path is not an existing regular file",
+        ));
     }
 
     let mut reader = fs::File::open(from)?;
@@ -21,11 +23,7 @@ pub fn copy(from: &Path, to: &Path) -> io::Result<u64> {
 
 pub fn remove_dir_all(path: &Path) -> io::Result<()> {
     let filetype = fs::symlink_metadata(path)?.file_type();
-    if filetype.is_symlink() {
-        fs::remove_file(path)
-    } else {
-        remove_dir_all_recursive(path)
-    }
+    if filetype.is_symlink() { fs::remove_file(path) } else { remove_dir_all_recursive(path) }
 }
 
 fn remove_dir_all_recursive(path: &Path) -> io::Result<()> {