withLatestFrom does not emit with synchronous source

[kwonoj]

Bug Report

https://stackblitz.com/edit/rxjs-bavruf?file=index.ts

of(1, 2, 3)
  .pipe(withLatestFrom(of(4, 5)))
  .subscribe(x => {
    console.log(x);
  });

does not emit anything. Looks like refactored implementation's control flag

rxjs/src/internal/operators/withLatestFrom.ts

Line 160 in 0b12f1a

let ready = false;

and others preventing subscribing into sync sources.

Current Behavior
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Reproduction

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Expected behavior
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Environment

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Possible Solution

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