Open chrome prior to system tests (PR #14260)
Theory: Chrome is busy with post install tasks, so start Chrome in
the background ahead of the tests.
Use the same arguments to start Chrome as the system tests,
some arguments are only observed for the first start of Chrome.
The first Chrome system test to run occasionally fails.
This has been observed on developer machines after chrome
updates, but is difficult to reproduce.
When this occur the NVDA logs indicate that a no virtual buffer is
created.
It isn't known if this is a bug in Chrome or NVDA.
The problem does not seem to affect users frequently, and when it
does recovery is possible by waiting a few seconds before switching
to another app and then back to Chrome.
The system tests failing has an impact on NVDA development,
requiring confirmation of the cause of failed tests, re-running
builds, and lowered confidence in automated testing.
