Google Vision barcode library not found

It started working after I cleared cache and freed up some space. I had "only" 400mb free space and there was no error message which would indicate that.

Google has confirmed a bug that they will fix soon, which prevents you in some cases to use this library of barcode/face-detection (link here) :

• A service required by Mobile Vision is now disabled due to a serious bug in that service. This will prevent users who have not already used face or barcode detection from using those features. We do not recommend adding new Mobile Vision features to your app until this issue is fixed.
• For apps that already use Mobile Vision features, check FaceDetector.isOperational() or BarcodeDetector.isOperational() to confirm detector readiness before using the face or barcode detector.

It's also written in some issues reported on Google's github sample repo:

https://github.com/googlesamples/android-vision/issues

Example (here) :

There is a known issue with the new version of GMSCore (v9) that was just released today.