merge revision(s) 40232: [Backport #8251]

	* test/drb/drbtest.rb (Drb{Core,Ary}#teardown): retry Process.kill
	  if it fails with Errno::EPERM on Windows (workaround).
	  [ruby-dev:47245] [Bug #8251]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@42090 b2dd03c8-39d4-4d8f-98ff-823fe69b080e