### 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
```
case ElementTypeClass:
        if (idToContextsMap !== null) {
          const id = getFiberID(getPrimaryFiber(fiber));
          const prevContexts = idToContextsMap.has(id)
            ? idToContextsMap.get(id)
            : null;
          const nextContexts = getContextsForFiber(fiber);
          if (prevContexts == null || nextContexts == null) {
            return null;
          }
          const [prevLegacyContext, prevModernContext] = prevContexts;
          const [nextLegacyContext, nextModernContext] = nextContexts;
          if (nextLegacyContext !== NO_CONTEXT) {
            return getChangedKeys(prevLegacyContext, nextLegacyContext);
          } else if (nextModernContext !== NO_CONTEXT) {
            return prevModernContext !== nextModernContext;
          }
        }
        break;
      default:
        break;
    }