test/ripper/test_scanner_events.rb: fill empty test methods

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@46949 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
parse.y: quoted label

* parse.y (assoc): allow quoted labels in hash literals.
  [ruby-core:34453] [Feature #4276]