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.)
export const enableProfilerCommitHooks = __PROFILE__;
export const enableProfilerNestedUpdatePhase = __PROFILE__;
export const enableProfilerNestedUpdateScheduledHook =
  __PROFILE__ && dynamicFeatureFlags.enableProfilerNestedUpdateScheduledHook;
export const enableSchedulingProfiler = __PROFILE__;
export const enableSchedulerTracing = true;
export const enableSchedulerDebugging = true;
export const warnAboutDeprecatedLifecycles = true;
export const disableLegacyContext = __EXPERIMENTAL__;
export const warnAboutStringRefs = false;
export const warnAboutDefaultPropsOnFunctionComponents = false;
export const enableSuspenseServerRenderer = true;
export const enableSelectiveHydration = true;
export const enableLazyElements = true;
export const disableJavaScriptURLs = true;
export const disableModulePatternComponents = true;
export const enableCreateEventHandleAPI = true;
export const enableFundamentalAPI = false;
export const enableScopeAPI = true;
export const warnAboutUnmockedScheduler = true;
export const enableSuspenseCallback = true;
export const enableComponentStackLocations = true;
export const disableTextareaChildren = __EXPERIMENTAL__;
export const warnUnstableRenderSubtreeIntoContainer = false;
export const enableDiscreteEventFlushingChange = true;
export const enableNewReconciler = __VARIANT__;
export const enableRecursiveCommitTraversal = false;
type Check<_X, Y: _X, X: Y = _X> = null;
(null: Check<ExportsType, FeatureFlagsType>);