In ruby/psych#292 I removed a couple uses of deprecated JRuby APIs. One of those, accessing RubyException.message directly, prevents us from removing that field. Once Psych is released with my changes, we can update it in JRuby and proceed to re-hide RubyException.message again.
Update Psych to 2.2.1. Fixes #4196.
Re-encapsulate message RubyException.message field. See #4196.
Revert "Update Psych to 2.2.1. Fixes #4196."
This reverts commit 36fb12d.
Psych 2.2.1 is busted because changes I made to support snakeyaml 1.17 were reverted. See ruby/psych#305.
Update to Psych 2.2.2. See ruby/psych#305
Fixes #4196 again.