The implementation also includes a Relax NG schema and tests for the schema
itself. The schema is used in c-index-test to verify that XML documents we
produce are valid. In order to do the validation, we add an optional libxml2
dependency for c-index-test.
Credits for CMake part go to Doug Gregor. Credits for Autoconf part go to Eric
Christopher. Thanks!
llvm-svn: 161431
Dmitri Gribenko