script: add CanGc as argument to VirtualMethods::children_changed
Testing: These changes do not require tests because they are a refactor.
Addresses part of https://github.com/servo/servo/issues/34573
Signed-off-by: Yerkebulan Tulibergenov <yerkebulan@gmail.com>
Creating elements by directly calling their interface constructors leads
to some state not being intialized correctly (see #39285). It is also
not in line with the specifications as many of them refer to the
[`create an element`][1] algorithm when an element needs to be created,
which directly maps to `Element::create` in the script crate.
So, switch all such places where elements are created by script to use
`Element::create`.
[1]: https://dom.spec.whatwg.org/#concept-create-element
Testing: Existing WPT tests.
Fixes: #39285
Signed-off-by: Mukilan Thiyagarajan <mukilan@igalia.com>
