This allows the garbage collector to keep HTML::Script objects alive and
fixes a bug where a HTMLScriptElement could get GC'd while its code was
executing.
This namespace will be used for all interfaces defined in the URL
specification, like URL and URLSearchParams.
This has the unfortunate side-effect of requiring us to use the fully
qualified AK::URL name whenever we want to refer to the AK class, so
this commit also fixes all such references.
