We have a new, improved string type coming up in AK (OOM aware, no null
state), and while it's going to use UTF-8, the name UTF8String is a
mouthful - so let's free up the String name by renaming the existing
class.
Making the old one have an annoying name will hopefully also help with
quick adoption :^)
Well... sort of. This adds the function itself and all the scaffolding
from the ShadowRealm API (and basically completes its implementation).
However, we do not nearly have enough support for modules and imports,
so we currently pretend whatever was attempted to be imported failed -
once we have HostImportModuleDynamically it should be relatively easy to
complete the implementation.
