Add tests for worker constructors called from worker global scope

[fred-wang]

https://html.spec.whatwg.org/multipage/workers.html#dedicated-workers-and-the-worker-interface
https://html.spec.whatwg.org/multipage/workers.html#shared-workers-and-the-sharedworker-interface

We have trusted-types/worker-constructor.https.html for worker constructors, but IIUC all the new calls are done from the Window global scope.

cc @mbrodesser-Igalia @lukewarlow

[mbrodesser-Igalia]

SharedWorker is only exposed to Window, see the IDL definition of https://html.spec.whatwg.org/multipage/workers.html#shared-workers-and-the-sharedworker-interface. So only tests for Workers are required.

[mbrodesser-Igalia]

Fixed via above linked commit.