merge revision(s) r46441: [Backport #9946]

	* process.c (open): use UTF-8 version function to support
	  non-ascii path properly.  [ruby-core:63185] [Bug #9946]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@47324 b2dd03c8-39d4-4d8f-98ff-823fe69b080e