A bug in #21 causes the default configuration to be omitted from the xorg
merging process. This can cause users not using set-xorg-configuration or
service extensions to end up with a broken configuration.
Fixes#5267.
* tests/services/xorg.scm: Add a regression test.
* gnu/services/xorg.scm (handle-xorg-configuration): Include the
xorg-configuration record from config in merges.
Change-Id: I6bed8c109057cb9b5de36db68b78e3ccc88e6bcb
Signed-off-by: Efraim Flashner <efraim@flashner.co.il>