name of the system property defining root workdir direcory
- it must be set before running tests using workdir
- in the case of running tests from XTest framework, this
property is set by the framework itself
- otherwise the default is ${java.io.tmpdir}/tests
Normalize java.io.File, that is make sure that returned File has
normalized case on Windows; that old Windows 8.3 filename is normalized;
that Unix symlinks are not followed; that relative path is changed to
absolute; etc.