Commit b8afa0abde9da31886a35f867d00a63a9cc69cc8 converted several interfaces
from NoInterfaceObject to mixins. It looks like it missed
HTMLHyperlinkElementUtils: it did update the interfaces that use
HTMLHyperlinkElementUtils (from "implements" to "includes"), but did not mark
HTMLHyperlinkElementUtils as a mixin.
Fix it, which makes HtmlAnchorElement gain useful functions like `set_href`.
* 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.
