image_to_vm.sh: make GPU sandbox failures non-fatal.

BUG=chromium:327824
TEST=Build VM, check session_manager_setup.sh and running processes for flag.
TEST=Trybots: lumpy, link, leon, daisy.
CQ-DEPEND=CL:190514

Change-Id: Idc898fbd638963efb564832d1008d3acaabd9383
Reviewed-on: https://chromium-review.googlesource.com/190792
Tested-by: Jorge Lucangeli Obes <jorgelo@chromium.org>
Reviewed-by: Antoine Labour <piman@chromium.org>
Commit-Queue: Jorge Lucangeli Obes <jorgelo@chromium.org>
1 file changed