merge revision(s) 54596:
* lib/irb/ext/save-history.rb: Fix NoMethodError when method is not defined.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@54597 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merge revision(s) 54596:
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_3@54597 b2dd03c8-39d4-4d8f-98ff-823fe69b080e