Reducer registration issue

[mfendeksilverstripe]

Looks like the reducer registration is not implemented correctly as it throws an error.

As far as I can see, this isn't functional error but we should fix that at some point.

Possible fix is to override the reducer instead of registering it.

Replace

Injector.reducer.register('versionedAdmin', combineReducers({
  historyViewer: historyViewerReducer,
}), { force: true });

With

Injector.transform(
  'versioned-history-viewer-override',
  (updater) => {
    updater.reducer('historyViewer', historyViewerReducer);
  }
);