merge revision(s) 42903: [Backport #8881]

	* class.c (method_entry_i): should exclude refined methods from
	  instance method list.  [ruby-core:57080] [Bug #8881]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@42924 b2dd03c8-39d4-4d8f-98ff-823fe69b080e