Patch XMLValidate to create a new parser every time, plus test case that verifies it works.
Note that there is an extra change, the return code of doVerify() is now boolean and not void. I have plans for an option to halt the build only if a schema is valid (I'm using ant/gump) to validate XSD files, and want to test that a schema correctly rejects invalid files. This is just a step on the way, while I was in the method.
git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@278246 13f79535-47bb-0310-9956-ffa450edef68