Open chrome prior to system tests
Theory: Chrome is busy with post install tasks, so start chrome in the
background ahead of the tests.
The first system test to run that requires chrome occasionally fails.
This has been replicated on developer machines after chrome updates,
however it is difficult to reproduce, and difficult to detect/recover-from
in an automated way.
It may be possible to handle this better within NVDA, however it seems
to actually affect users infrequently, and they seem to be able to
recover by waiting a few seconds and de/refocus chrome.
In the mean time, the system tests failing delays development.
