Function startWorkLoopTimer

code/third-party/public/app.js:6973–6986

(nextUnitOfWork)

}

function startWorkLoopTimer(nextUnitOfWork) {
  if (enableUserTimingAPI) {
    currentFiber = nextUnitOfWork;
    if (!supportsUserTiming) {
      return;
    }
    commitCountInCurrentWorkLoop = 0;
    // This is top level call.
    // Any other measurements are performed within.
    beginMark('(React Tree Reconciliation)');
    // Resume any measurements that were in progress during the last loop.
    resumeTimers();
  }
}

function stopWorkLoopTimer(interruptedBy) {
  if (enableUserTimingAPI) {