Sync web-platform-tests PR 23072 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/23072
Details from upstream follow.

Mason Freed <masonfreed@chromium.org> wrote:

Fix customized built-in element constructor behavior

This CL implements two changes:

1. It fixes the implementation to better match the spec for the
   "create an element for the token" [1] algorithm. Prior to this CL,
   step 7 of that algorithm was skipping directly to step 6 of the
   "create an element" [2] algorithm, skipping over step 5 for
   customized built-in elements. This is now fixed. This case is
   illustrated by the issue and example at [3] and [4]. This becomes
   the first test in customized-built-in-constructor-exceptions.html.

2. It updates the comments to match the new behavior discussed in [3]
   and the [5] spec PR, which changes the return value in the case
   that a customized built-in element constructor throws an exception.
   With the change above, that is actually already the behavior. So
   this is just a comment change. Two new tests are added to
   customized-built-in-constructor-exceptions.html.

[1] https://html.spec.whatwg.org/multipage/parsing.html#create-an-element-for-the-token
[2] https://dom.spec.whatwg.org/#concept-create-element
[3] https://github.com/whatwg/html/issues/5084
[4] https://crbug.com/1024866
[5] https://github.com/whatwg/dom/pull/797

Bug: 1071059, 1024866
Change-Id: I814c81991eb5e83501304bcb3d2da476743aef52
Cq-Do-Not-Cancel-Tryjobs: true
Reviewed-on: https://chromium-review.googlesource.com/2152986
WPT-Export-Revision: 14d2b4fe5e2361e065c0a0d3e16d9094da977202

CI Results

Ran 13 Firefox configurations based on mozilla-central, and Firefox, Chrome, and Safari on GitHub CI

Total 60 tests

Status Summary

Firefox

OK : 1
PASS : 3[GitHub] 62[Gecko-android-em-7.0-x86_64-debug-geckoview, Gecko-android-em-7.0-x86_64-opt-geckoview, Gecko-linux1804-64-asan-opt, Gecko-linux1804-64-debug, Gecko-linux1804-64-opt, Gecko-linux1804-64-qr-debug, Gecko-linux1804-64-qr-opt, Gecko-windows10-64-debug, Gecko-windows10-64-opt, Gecko-windows10-64-qr-debug, Gecko-windows10-64-qr-opt, Gecko-windows7-32-debug, Gecko-windows7-32-opt]

Chrome

CRASH: 1

Safari

OK : 1
FAIL : 3

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

https://hg.mozilla.org/mozilla-central/rev/f016ab30013b