merge revision(s) 44514: [Backport #9374]

	* ext/json/generator/depend: add build dependencies for json extension
	  [Bug #9374] [ruby-core:59609]

	* ext/json/parser/depend: ditto


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_1@45123 b2dd03c8-39d4-4d8f-98ff-823fe69b080e