Autotest: Look farther for machine killing tests.

Increase the cutoff for how far back in time we look to find the last test
ran on a repair failed machine to 60 mins past the max runtime for a job.

The job_max_runtime_mins_default specifies how long a job can run before timing
out. We look 60 mins past this to make sure we catch all the jobs without
looking at too many.

BUG=None
TEST=Manuel add in exception to repair code and unittests.

Change-Id: I7586f54ca9fa62bf16086942c7126ebb588d6044
Reviewed-on: https://gerrit.chromium.org/gerrit/64818
Reviewed-by: Dennis Jeffrey <dennisjeffrey@chromium.org>
Commit-Queue: Keyar Hood <keyar@chromium.org>
Tested-by: Keyar Hood <keyar@chromium.org>
2 files changed