Revert of [telemetry] Refactor run_tests to remove old cruft.

tools/perf/run_tests

Index: tools/perf/run_tests
diff --git a/tools/perf/run_tests b/tools/perf/run_tests
index ed1429cb7f9b5c84b51df529558b6d9010d1ab89..77a5366647e7cb6bd9fd0d7ae86ed2e0bf69455a 100755
--- a/tools/perf/run_tests
+++ b/tools/perf/run_tests
@@ -5,18 +5,24 @@
 
 """This script runs unit tests of the code in the perf directory.
 
-This script DOES NOT run benchmarks. run_benchmark and run_measurement do that.
+This script DOES NOT run benchmarks. run_benchmarks and run_measurement do that.
 """
 
 import os
 import sys
 
 sys.path.append(os.path.join(os.path.dirname(__file__), os.pardir, 'telemetry'))
-
+from telemetry.unittest import gtest_testrunner
 from telemetry.unittest import run_tests
 
 
 if __name__ == '__main__':
-  base_dir = os.path.dirname(os.path.realpath(__file__))
-  run_tests.environment = run_tests.Environment(base_dir, [base_dir])
-  sys.exit(run_tests.RunTestsCommand.main())
+  top_level_dir = os.path.abspath(os.path.dirname(__file__))
+  runner = gtest_testrunner.GTestTestRunner(print_result_after_run=False)
+  ret = run_tests.Main(sys.argv[1:], top_level_dir, top_level_dir, runner)
+
+  if runner.result:
+    runner.result.PrintSummary()
+    sys.exit(min(ret + runner.result.num_errors, 255))
+  else:
+    sys.exit(ret)