[tools/perf] Resolve the import error when record_wpr tries to discover benchmarks

BUG=581103

Review URL: https://codereview.chromium.org/1633143003

Cr-Commit-Position: refs/heads/master@{#371586}

tools/perf/record_wpr

@@ -6,12 +6,16 @@ import os
 import sys
 
 
+from core import path_util
 from chrome_telemetry_build import chromium_config
 sys.path.append(chromium_config.GetTelemetryDir())
 
 from telemetry import record_wpr
 
+# This is required to resolve importing davclient in tools/perf/third_party/
+# when record_wpr try to dynamically discover benchmark classes.
+import third_party  # pylint: disable=unused-import
+
 
 if __name__ == '__main__':
-  _perf_dir = os.path.dirname(__file__)
-  sys.exit(record_wpr.Main(_perf_dir))
+  sys.exit(record_wpr.Main(path_util.GetPerfDir()))

tools/perf/scripts_smoke_unittest.py

@@ -9,8 +9,6 @@ import sys
 import tempfile
 import unittest
 
-from telemetry import decorators
-
 
 class ScriptsSmokeTest(unittest.TestCase):
 
@@ -50,7 +48,6 @@ class ScriptsSmokeTest(unittest.TestCase):
     self.assertEquals(return_code, 0, stdout)
     self.assertIn('optional arguments:', stdout)
 
-  @decorators.Disabled('all')  # crbug.com/581103
   def testRunRecordWprList(self):
     return_code, stdout = self.RunPerfScript('record_wpr --list-benchmarks')
     # TODO(nednguyen): Remove this once we figure out why importing