function registerTwoPhaseEvent(
  registrationName: string,
  dependencies: Array<DOMEventName>,
): void {
  registerDirectEvent(registrationName, dependencies);
  registerDirectEvent(registrationName + 'Capture', dependencies);
}
Mapping from lowercase registration names to the properly cased version,
used to warn in the case of missing event handlers. Available
only in __DEV__.
@type {Object}