Make tests work with source-only libgoogletest.
Make tests work with source-only libgoogletest.

Debian distributes libgoogletest a.k.a. libgtest in source
form now, so update SConstruct to build it from
/usr/src/gtest/src.

Also, I am regretting using SCons so hard right now. :-(

derat/xsettingsd,derat/xsettingsd