Enable presubmit pylint in build/android.

build/android/pylib/perf/test_runner.py

 # Copyright 2013 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.
 
 """Runs perf tests.
 
 Our buildbot infrastructure requires each slave to run steps serially.
 This is sub-optimal for android, where these steps can run independently on
 multiple connected devices.
 
@@ skipping 211 matching lines @@
 
   def RunTest(self, test_name):
     """Run a perf test on the device.
 
     Args:
       test_name: String to use for logging the test result.
 
     Returns:
       A tuple of (TestRunResults, retry).
     """
-    output, result_type = self._LaunchPerfTest(test_name)
+    _, result_type = self._LaunchPerfTest(test_name)
     results = base_test_result.TestRunResults()
     results.AddResult(base_test_result.BaseTestResult(test_name, result_type))
     retry = None
     if not results.DidRunPass():
       retry = test_name
     return results, retry