Rename URLUtils interface as HTMLHyperlinkElementUtils and update.

third_party/WebKit/Source/core/html/HTMLHyperlinkElementUtils.idl

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// https://html.spec.whatwg.org/#htmlhyperlinkelementutils
+
+[
+    NoInterfaceObject, // Always used on target of 'implements'
+] interface HTMLHyperlinkElementUtils {
+    stringifier attribute USVString href;
+    [NotEnumerable, ImplementedAs=href] USVString toString();

[sof, 2016/04/19 10:01:31]

I can't say I understand why this toString() is needed, but not on URL. (see
ps#1 for what happens if you leave it out.)

[sof, 2016/04/19 11:05:15]

https://codereview.chromium.org/1901983002/ mostly addresses this infelicity
(modulo NotEnumerable)

[sof, 2016/04/19 11:51:59]

We should try to address not having enumerable toString()s, which prevents the
use of 'stringifier', but not here. Added TODOs.

+    readonly attribute USVString origin;
+
+    attribute USVString protocol;
+    attribute USVString username;
+    attribute USVString password;
+    attribute USVString host;
+    attribute USVString hostname;
+    attribute USVString port;
+    attribute USVString pathname;
+    attribute USVString search;
+    attribute USVString hash;
+};