Hello again -- a couple of newbie questions

Hey again,

Thanks again everybody for your help. I've been working on some of the
tests listed here:
https://github.com/w3c/web-platform-tests/labels/difficulty%3Aeasy I
finished a couple and I'm procrastinating on doing a pull request. But in
the meantime, I have a couple of questions about two other tests:

-  #1509, Test that innerHTML works in synthetic documents. (
https://github.com/w3c/web-platform-tests/issues/1509) It's not clear to me
what synthetic documents are. The issue description mentions documents
created with createHTMLDocument. Is that the only way to create a synthetic
document, or are there others?

-  #1527, Add more extensive tests for crypto.getRandomValues(). (
https://github.com/w3c/web-platform-tests/issues/1527) What is the correct
way to handle zero-sized arrays?

Thanks,

Chris