### Describe what you were doing when the bug occurred:
1. I did profiling on a list, that gets updated on each pagination api call.
2. Once the profiling was done, I moved around in the Profiler to view the Flamegraph
3. Moving to second capture, the Profiler crashed.


**DevTools version**: 4.6.0-6cceaeb67

```
Component stack: in ec
    in div
    in div
    in div
    in So
    in Unknown
    in n
    in Unknown
    in div
    in div
    in rl
    in Ze
    in fn
    in Ga
    in _s
```
}
  function mountFiberRecursively(
    firstChild: Fiber,
    parentFiber: Fiber | null,
    traverseSiblings: boolean,
    traceNearestHostComponentUpdate: boolean,
  ) {
     Iterate over siblings rather than recursing.
     This reduces the chance of stack overflow for wide trees (e.g. lists with many items).
    let fiber: Fiber | null = firstChild;
    while (fiber !== null) {
      if (__DEBUG__) {
        debug('mountFiberRecursively()', fiber, parentFiber);
      }
       If 
       Als
      const mightSiblingsBeOnTrackedPath = updateTrackedPathStateBeforeMount(
        fiber,
      );
      const shouldIncludeInTree = !shouldFilterFiber(fiber);
      if (shouldIncludeInTree) {
        recordMount(fiber, parentFiber);
      }
      if (traceUpdatesEnabled) {
        if (traceNearestHostComponentUpdate) {
          const elementType = getElementTypeForFiber(fiber);
           If 
          if (elementType === ElementTypeHostComponent) {
            traceUpdatesForNodes.add(fiber.stateNode);
            traceNearestHostComponentUpdate = false;