merge revision(s) 42450: [Backport #8735]

	* enumerator.c (lazy_zip_func): fix non-single argument.  fix
	  out-of-bound access and pack multiple yielded values.
	  [ruby-core:56383] [Bug #8735]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@42922 b2dd03c8-39d4-4d8f-98ff-823fe69b080e