Converts the request options into the init shape a platform's native fetch accepts. A
platform can declare its AbortSignal as a lexical class, which AbortSignalLike
cannot resolve to, so the signal member widens here. The caller must pass a signal
created by the running platform. The widening then only restores the type the runtime
already has.
Converts the request options into the init shape a platform's native
fetchaccepts. A platform can declare itsAbortSignalas a lexical class, whichAbortSignalLikecannot resolve to, so thesignalmember widens here. The caller must pass a signal created by the running platform. The widening then only restores the type the runtime already has.