--with-Xdummy --with-Xdummy_wrapper options not honored across invocations of setup.py

[jonathan.underwood]

It used to be the case that you could specify --with-Xdummy --with-Xdummy_wrapper when running setup.py build to force selection of the Xdummy wrapper rather than Xvfb without having the Xorg detection stuff kick in. Subsequently, running a python setup.py --skip-build install (without --with-Xdummy --with-Xdummy_wrapper) would install an xpra.conf file which used Xdummy, as expected.

Currently, unless --with-Xdummy --with-Xdummy_wrapper is specified both with build and install, the Xorg detection stuff kicks in during install, and a xpra.conf using Xvfb is installed.

Logically, I expect xpra.conf to be created during build, and whatever is present during install is just installed if we're using --skip-build. I'm not sure when this crept in.

[Antoine Martin]

out of time, and this stuff is always harder than it looks - rescheduling

see also #977

[Antoine Martin]

Too hard to fix for little gain.