Try to enable all webidls (#573)

* Try to enable all webidls

* Separate out unavailable webidl files by reason.

* Create record of fully tested WebIDL files

* Update notes to reflect new situation with web-idl

* Make a blank ident fail, disable the necessary widls.

It turns out that all the blank idents came from blank enum variants,
which is allowed in webidl apparently.

crates/web-sys/webidls/enabled/TextEncoder.webidl

@@ -0,0 +1,28 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * The origin of this IDL file is
+ * http://encoding.spec.whatwg.org/#interface-textencoder
+ *
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+[Constructor,
+ Exposed=(Window,Worker,System)]
+interface TextEncoder {
+  [Constant]
+  readonly attribute DOMString encoding;
+  /*
+   * This is spec-wise USVString but marking it as
+   * DOMString to avoid duplicate work. Since the
+   * UTF-16 to UTF-8 converter performs processing
+   * that's equivalent to first converting a
+   * DOMString to a USVString, let's avoid having
+   * the binding code doing it, too.
+   */
+  [NewObject]
+  Uint8Array encode(optional DOMString input = "");
+};