(Regarding the experimental `React.unstable_Profiler` API and reactjs/rfcs/pull/51.)

PR #13058 changed the behavior of React profiling builds to opt host roots into `ProfileMode` if the React DevTools extension is detected. This was necessary in order to have accurate tree base time measurements for the visual flame graphs.

The Profiler plug-in for DevTools does feature detection to determine if it's enabled by looking at each root and seeing if any of the fibers contain an `actualDuration` attribute,

The problem is that the `actualDuration` attribute will be present on v16.4 fibers, which pre-date PR #13058. As a result, the Profiler UI may enable itself with versions of React that it cannot work correctly with.

Perhaps an easy solution would be to rename one of the `unstable_Profiler`'s fiber attributes prior to the next minor release (e.g. `treeBaseTime` -> `treeBaseDuration`) and change the DevTools Profiler to feature check using this new name instead.
stopCommitLifeCyclesTimer,
} from './ReactDebugFiberPerf';
import {createWorkInProgress, assignFiberPropertiesInDEV} from './ReactFiber';
import {onCommitRoot} from './ReactFiberDevToolsHook';
import {
  NoWork,
  Sync,
  Never,
  msToExpirationTime,
  expirationTimeToMs,
  computeAsyncExpiration,
  computeInteractiveExpiration,
} from './ReactFiberExpirationTime';
import {AsyncMode, ProfileMode} from './ReactTypeOfMode';
import {enqueueUpdate, resetCurrentlyProcessingQueue} from './ReactUpdateQueue';
import {createCapturedValue} from './ReactCapturedValue';
import {
  popTopLevelContextObject as popTopLevelLegacyContextObject,
  popContextProvider as popLegacyContextProvider,
} from './ReactFiberContext';
import {popProvider} from './ReactFiberNewContext';
import {popHostContext, popHostContainer} from './ReactFiberHostContext';
import {
  checkActualRenderTimeStackEmpty,
  pauseActualRenderTimerIfRunning,
  recordCommitTime,
  recordElapsedActualRenderTime,
  recordElapsedBaseRenderTimeIfRunning,
  resetActualRenderTimerStackAfterFatalErrorInDev,
  resumeActualRenderTimerIfPaused,