port tests to python3

[Martin Pitt]

We should move the autopilot tests to python 3.

[Martin Pitt (pitti)]

This is my current patch which attemps to do that. However, it fails with

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/autopilot/utilities.py", line 351, in action_on_test_end
    obj.on_test_end(test_instance)
  File "/usr/lib/python3/dist-packages/autopilot/input/_X11.py", line 493, in on_test_end
    move_mouse_to_screen(0)
  File "/usr/lib/python3/dist-packages/autopilot/display/__init__.py", line 59, in move_mouse_to_screen
    Mouse.create().move(x, y, False)
  File "/usr/lib/python3/dist-packages/autopilot/input/__init__.py", line 298, in create
    return _pick_backend(backends, preferred_backend)
  File "/usr/lib/python3/dist-packages/autopilot/utilities.py", line 65, in _pick_backend
    "Unable to instantiate any backends\n%s" % '\n'.join(failure_reasons))
RuntimeError: Unable to instantiate any backends
X11: DisplayConnectionError(':99', b'No protocol specified\n')
}}}

python3-evdev and python3-xlib are installed, so I don't have a good idea what's wrong here. Attaching the patch here to avoid losing it, as I need to stop working on this now.

[Martin Pitt (pitti)]

I know what's wrong. We need https://code.launchpad.net/~pitti/autopilot/sandbox-run/+merge/219982 to land in the distro before we can port this to py3.