runner.rb: include event name

* test/runner.rb (after_teardown): include active trace event name
  in the failure message.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46431 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* 2014-06-15

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46432 b2dd03c8-39d4-4d8f-98ff-823fe69b080e