It needs to be called as early as possible before unit tests
has a chance to import gtk.
Hopefully will fix random test failures we are seeing in buildbot.
This ensures the test itself is not recognized as a client
by the registry. I'm not sure how that happens since we are
not loading gtk, but it does. Not being a real gtk client with
a mainloop we wasn't answering dbus calls and causing the registry
to hang and fail.
Development continued there for a while. Now I will remove it
and used the toolkit implementation instead.
Changes:
* Retry faster
* Handle GLib errors
* Don't always dump the tree
* Support master atspi api
The uitree module exposes the at-spi tree. We can use it to do
functional tests of the UI, by checking if the expected
widgets exists, clicking them etc.
A simple example of how this can be used is in the test, which
runs a window and check that it has the expected button.
