Robustify starting a VM to ensure it is ssh-able.

This CL adds the logic from retry_until_ssh in cros_vm_lib.sh in
in crosutils. This is added there and needs to be added here because
when sshing into a VM while a machine is under heavy load ssh can hang
due to an SSH bug.

BUG=chromium:209719
TEST=Ran it multiple times + pyflakes + pylint

Change-Id: I0228a540eb531b41f9e69e3e5a4f8df416da1935
Reviewed-on: https://gerrit.chromium.org/gerrit/60921
Tested-by: Chris Sosa <sosa@chromium.org>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Commit-Queue: Chris Sosa <sosa@chromium.org>
1 file changed