Convert most graphics_ui_test to test.test.

This gets rid of dependencies on Chrome and in particular pyauto. We introduce
graphics_utils.py to keep GPU state checking functionality.

BUG=chromium:271828
TEST=Ran all affected graphics_* tests.

Change-Id: Iee9971d292bd6405a92f0ee5d13d5c032f657998
Reviewed-on: https://gerrit.chromium.org/gerrit/66133
Commit-Queue: Ilja H. Friedel <ihf@chromium.org>
Reviewed-by: Ilja H. Friedel <ihf@chromium.org>
Tested-by: Ilja H. Friedel <ihf@chromium.org>
8 files changed