function findNumericNodeHandleFiber(componentOrHandle) {
  var instance = findNodeHandle(componentOrHandle);
  if (instance == null || typeof instance === "number") {
    return instance;
  }
  return instance._nativeTag;
}
External users of findNodeHandle() expect the host tag number return type.
The injected findNodeHandle() strategy returns the instance wrapper though.
See NativeMethodsMixin#setNativeProps for more info on why this is done.