merge revision(s) 43110,43155: [Backport #8768]

	* lib/tempfile.rb (Tempfile#unlink): finalizer is no longer needed
	  after unlinking.  patched by by normalperson (Eric Wong) at
	  [ruby-core:56521] [Bug #8768]


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_0_0@43229 b2dd03c8-39d4-4d8f-98ff-823fe69b080e