Drupal 8 Symfony validator update

Drupal 8 needed to move its typed-data validation code from the Symfony 2.4 API to the Symfony 2.5+ API. The change was tracked as a critical Drupal core issue.

What I contributed

I took the issue, submitted two patch revisions, and moved the validator configuration to the Symfony 2.5 API. I also started the metadata interface update from PropertyMetadataContainerInterface to ClassMetadataInterface and recorded the remaining test work for the next contributor.

Result

The issue continued as a shared effort across the Drupal community. The final Drupal core commit, committed on May 5, 2015, credits my Drupal.org username, Miroling, with the other contributors. The issue record was closed as fixed on May 20, 2015.