emberjs/ember.js — pull request #9899 by ghempton (2014-12-12 23:00:55+00:00)
Title: [BUGFIX release] Re-enable runtime 'mandatory-setter' feature flag

Fixes #9897. The one caveat here is that `mandatory-setter` feature is *enabled* by default in development– this goes contrary to most features being *disabled* by default. Alternatively, this feature could be renamed `skip-mandatory-setter`.