Alp Mestanogullari authored Nov 01, 2019 and Marge Bot committed Nov 07, 2019

Before this patch, Hadrian didn't care about the TEST_ENV and
METRICS_FILE environment variables, that the performance testing
infrastructure uses to record perf tests results from CI jobs.

It now looks them up right before running the testsuite driver,
and passes suitable --test-env/--metrics-file arguments when
these environment variables are set.