mark Hash keys correctly.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58452 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
mark Hash keys correctly.
Newly created frozen objects are not referred from any roots/objects.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@58452 b2dd03c8-39d4-4d8f-98ff-823fe69b080e