Intent to ship: <input type=file webkitdirectory> and webkitEntries API on Android

[Makoto Kato]

Hello,

Gecko can use webkitdirectory attribute and webkitEntries API to
choose file directory on the desktop version only. I intend to enable
this attribute and file entries API on Firefox Android.

Bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1887878
<https://bugzilla.mozilla.org/show_bug.cgi?id=1887878>
Specification:
https://wicg.github.io/entries-api/#dom-htmlinputelement-webkitdirectory
<https://wicg.github.io/entries-api/#dom-htmlinputelement-webkitdirectory>
(WHATWG issue is https://github.com/whatwg/html/issues/217
<https://github.com/whatwg/html/issues/217>)
Standards Body: WICG
Platform coverage: All. Desktop already turned on.
Preference: dom.webkitBlink.dirPicker.enab

led and
dom.webkitBlink.filesystem.enabled
DevTools: Not needed
Other browsers:
  Blink: Shipped
  WebKit: Shipped.
web-platform-tests:
https://wpt.fyi/results/testing/web-platform/tests/interfaces/entries-api.idl
<https://wpt.fyi/results/testing/web-platform/tests/interfaces/entries-api.idl>

-- Makoto