Fix https://issues.apache.org/bugzilla/show_bug.cgi?id=55664
Correctly handle Encoder, Decoder and MessageHandler implementations that use a generic type such as Encoder.Text<List<String>>

git-svn-id: https://svn.apache.org/repos/asf/tomcat/trunk@1533347 13f79535-47bb-0310-9956-ffa450edef68