[tools/perf] Remove default values of benchmark_dirs and top_level_dir in chromium_config module (R…

tools/perf/run_telemetry_tests

 #!/usr/bin/env python
 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """This script runs unit tests of the code in the perf directory.
 
 This script DOES NOT run benchmarks. run_benchmark does that.
 """
 
 import os
 import subprocess
 import sys
 
 from chrome_telemetry_build import chromium_config
+from core import path_util
+path_util.AddTelemetryToPath()
 
-
-sys.path.append(chromium_config.GetTelemetryDir())
 from telemetry.testing import unittest_runner
 
 
 def main():
   telemetry_test_config = os.path.join(
-      chromium_config.GetTelemetryDir(), 'telemetry',
+      path_util.GetTelemetryDir(), 'telemetry',
       'telemetry_unittest_deps.json')
   project_config = chromium_config.ChromiumConfig(
-      top_level_dir=chromium_config.GetTelemetryDir(),
+      top_level_dir=path_util.GetTelemetryDir(),
       client_configs=[chromium_config.CLIENT_CONFIG_PATH, telemetry_test_config]
   )
   return unittest_runner.Run(
       project_config, disable_cloud_storage_io_during_test=True)
 
 if __name__ == '__main__':
   sys.exit(main())