Add source information to parse exception on no close tag error.
[Bug #8844] [ruby-dev:47672]
Patch by Ippei Obayashi. Thanks!!!
* test/rexml/parser/test_tree.rb: Add a test for the above case.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@42815 b2dd03c8-39d4-4d8f-98ff-823fe69b080e