Sandbox: https://codesandbox.io/s/cranky-kapitsa-op3jh

Repro: type "a" and then after a second "b"

Expected: Eventually you'll see "ab" in all fields. Pending "..." indicator goes away.

Actual: You'll keep seeing "a" in low pri field. Pending "..." indicator is stuck.
expect(ReactNoop.getChildren()).toEqual([
        span('A: 2, B: 3, C: [not loaded]'),
      ]);
      ReactNoop.render(<App loadC={true} />);
      expect(() => {
        expect(() => {
          expect(Scheduler).toFlushAndYield(['A: 2, B: 3, C: 0']);
        }).toThrow('Rendered more hooks than during the previous render');
      }).toErrorDev([
        'Warning: React has detected a change in the order of Hooks called by App. ' +
          'This will lead to bugs and errors if not fixed. For more information, ' +
          'read the Rules of Hooks: https://fb.me/rules-of-hooks\n\n' +
          '   Previous render            Next render\n' +
          '   ------------------------------------------------------\n' +
          '1. useState                   useState\n' +
          '2. useState                   useState\n' +
          '3. undefined                  useState\n' +
          '   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^\n\n',
      ]);
      
      
      
      
      
    });
    it('unmount state', () => {
      let updateA;
      let updateB;
      let updateC;
      function App(props) {