* lib/rexml/source.rb (REXML::IOSource#encoding_updated): Fix a
  bug that can't parse XML correctly when
  Encoding.default_internal is different with XML
  encoding. REXML::Source converts XML encoding on read. So IO
  should not convert XML encoding.
  Based on patch by NAKAMURA Usaku.
  [ruby-dev:48686] [Bug #10418]

* test/rexml/test_encoding.rb
  (REXMLTests::EncodingTester#test_parse_utf16_with_utf8_default_internal):
  Add the for the above case.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48109 b2dd03c8-39d4-4d8f-98ff-823fe69b080e