Install version 6.0.0+ of RNN. Run on IOS and the error should appear.
Error:

hmm this file was indeed deleted in v6. Are you using the old shared element api? if not, try resetting cache when running the packager: npm run start -- --reset-cache
@guyca I have another issue when I click the SharedElement demo it crashes.

@bang88 @TylerNRobertson I wasn't able to reproduce this on a fresh clone. This leads me to think it's a caching issue. Please try starting the packager with watchman watch-del-all && npm run start -- --reset-cache.
@guyca you were right caching issue. Thanks!
Came here after hitting the same issue on an RNN upgrade effort to v6. Can confirm that these steps to restart and clear package manager resolved the issue:
Please try starting the packager with watchman watch-del-all && npm run start -- --reset-cache
Most helpful comment
Came here after hitting the same issue on an RNN upgrade effort to v6. Can confirm that these steps to restart and clear package manager resolved the issue: