Test Runner: Prevent race by not resetting timeout.
Test Runner: Prevent race by not resetting timeout.

This instead only sets the timeout when tests start to run. That
way the timeout should always be at least the default timeout
and we won't get into a situation where the watchdog times out
the test immediately when the test starts.

Bug: angleproject:5562
Change-Id: I6b12bb8fe8edcf35f46ba4fb106fdf80ff9402a1
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2637182
Reviewed-by: Yuly Novikov <36f5580f63d0a3eacc17e89a61d11e2f646630d2@chromium.org>
Commit-Queue: Jamie Madill <7e492b4f1c8458024932de3ba475cbf015424c30@chromium.org>

ppy/angle,ppy/angle,ppy/angle,ppy/angle