autotest: add hasty mode to GLMark2.

This gets rid of validation mode. Instead we will run each subtest at 2s
by default, in hasty mode (used for bvt-cq) only 0.2s. This saves about
5 minutes of time in the cq, but still exerises the graphics pipeline.

Note this will impact the graphs on the perf dashboard.

BUG=chromium:427641
TEST=time bin/autotest tests/graphics_GLMark2/control.bvt-cq
     real	0m21.634s
     time bin/autotest tests/graphics_GLMark2/control
     real	1m19.568s

Change-Id: I55902724f8fb3bcf22a86dba184d6b2852934b05
Reviewed-on: https://chromium-review.googlesource.com/226006
Tested-by: Ilja Friedel <ihf@chromium.org>
Reviewed-by: Haixia Shi <hshi@chromium.org>
Commit-Queue: Ilja Friedel <ihf@chromium.org>
3 files changed