Make the `enableSchedulingProfiler` flag dynamic for the profiling build (so marks can be disabled). I think it should be sufficient to do something like:
```js
export const enableSchedulingProfiler =
  __PROFILE__ && dynamicFeatureFlags.enableSchedulingProfiler;
```

Update our User Timing API check to include `clearMeasures` and when we call `mark(name)`, also call `clearMeasures(name)` to avoid clogging the entries buffer. (Apparently this has a significant negative performance impact for Firefox.)
this.forceUpdate();
      }
      render() {
        return null;
      }
    }
    ReactTestRenderer.create(<Example />, {unstable_isConcurrent: true});
    expect(marks).toEqual([
      `--react-init-${ReactVersion}`,
      '--schedule-render-512',
    ]);
    marks.splice(0);
    expect(Scheduler).toFlushUntilNextPaint([]);
    expect(marks).toEqual([
      '--render-start-512',
      '--render-stop',
      '--commit-start-512',
      '--layout-effects-start-512',
      '--schedule-forced-update-1-Example',
      '--layout-effects-stop',
      '--render-start-1',
      '--render-stop',
      '--commit-start-1',
      '--commit-stop',
      '--commit-stop',
    ]);
  });
  
  it('should mark render phase state updates for class component', () => {
    class Example extends React.Component {