[ServiceWorker] Use SyntaxError when an URL can't be parsed in Clients.openWindow() (#619)

A lot of specifications uses SyntaxError for that purpose. The only ones that don't are URL and Fetch. I still do not understand why we want to move all errors to TypeError. Meaningful error are for the best.

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Reply to this email directly or view it on GitHub:
https://github.com/slightlyoff/ServiceWorker/issues/619