Daemon may take some moments to do IO operations, and the tests
may be too fast in reading this.
As per previous cleanups this become a problem when testing in
slower scenarios (as valgrind), so take the opportunity to
cleanup the tests so that we always wait for file contents to
match the expected one.
Some systems have multiple GPUs with an eDP output but the panel
isn't connected to all of them (or it's controlled by a mux).
Handle this case by ensuring that the panel is connected when
before writing an attribute.
Expose the daemon as 'org.freedesktop.UPower.PowerProfiles' by default
but we also own the old 'net.hadess.PowerProfiles' name for
compatibility resons.
Also dbus objects are now registered also in the path
/org/freedesktop/UPower/PowerProfiles and they implement the
org.freedesktop.UPower.PowerProfiles interface.
Even in this case we preserve the compatibility with the old ones.
To make this switch as most reliable as possible, the code is now
generated for dbus configuration files preserving the previous ones as
base.
Tests are now performed checking both names, to ensure again that we're
not breaking the expectations for the old APIs consumers.
