Write unit tests for soy.Client.window, specifically testing resizing, changing position, and fullscreen mode.

These tests may need to use Python's ctypes module to access window geometry X11 directly. A big part of these tests will be to check against different window managers and display setups.

While working on this task you should join and remain in #CopyleftGames on Freenode to get help, feedback, and guidance from mentors and other developers. Code updates which may affect your work are also announced here as they happen.

When you've done, commit your work and post the resulting changeset url to this task.