fix: skip non-UTF-8 dir entries in Deno.readDir() (denoland#4004)

Example:

		$ python2 -c 'open("\x80\x7F", "w")'

		$ deno eval 'Deno.readDirSync(".")'
		thread 'main' panicked at 'called `Option::unwrap()` on a `None` value', cli/ops/fs.rs:373:16
		note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
		fatal runtime error: failed to initiate panic, error 5
		Aborted (core dumped)

Before this commit they made deno panic, now they are silently skipped.
Not ideal but arguably better than panicking.

No test because what characters are and aren't allowed in filenames is
highly file system-dependent.

Closes denoland#3950

cli/ops/fs.rs

@@ -365,14 +365,16 @@ fn op_read_dir(
  blocking_json(is_sync, move || {
  debug!("op_read_dir {}", path.display());
  let entries: Vec<_> = fs::read_dir(path)?
- .map(|entry| {
+ .filter_map(|entry| {
  let entry = entry.unwrap();
  let metadata = entry.metadata().unwrap();
- get_stat_json(
- metadata,
- Some(entry.file_name().to_str().unwrap().to_owned()),
- )
- .unwrap()
+ // Not all filenames can be encoded as UTF-8. Skip those for now.
+ if let Some(filename) = entry.file_name().to_str() {
+ let filename = Some(filename.to_owned());
+ Some(get_stat_json(metadata, filename).unwrap())
+ } else {
+ None
+ }
  })
  .collect();