- Enable unsigned-integer-overflow and float-divide-by-zero sanitizers.
- Disable some unneeded libxml2 components.
- Disable debugging and profiling code in libxslt to improve
coverage stats.
I added dominicc@chromium.org and ddkilzer@apple.com to auto_ccs.
They're already listed in libxml2's project.yaml and I worked with both
of them when reporting libxslt issues in the past.