[Android] Make android test runner run perf tests in alphabetical order.

build/android/pylib/local/device/local_device_perf_test_run.py

 # 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.
 
+import collections
 import io
 import json
 import logging
 import os
 import pickle
 import shutil
 import tempfile
 import threading
 import time
 import zipfile
@@ skipping 348 matching lines @@
                                                            steps['version']))
         return steps
     raise PerfTestRunGetStepsError(
         'Neither single_step or steps set in test_instance.')
 
   def _SplitTestsByAffinity(self):
     # This splits tests by their device affinity so that the same tests always
     # run on the same devices. This is important for perf tests since different
     # devices might yield slightly different performance results.
     test_dict = self._GetStepsFromDict()
-    for test, test_config in test_dict['steps'].iteritems():
+    for test, test_config in sorted(test_dict['steps'].iteritems()):
       try:
         affinity = test_config.get('device_affinity')
         if affinity is None:
           self._no_device_tests[test] = test_config
         else:
           if len(self._test_buckets) < affinity + 1:
             while len(self._test_buckets) != affinity + 1:
-              self._test_buckets.append({})
+              self._test_buckets.append(collections.OrderedDict())
           self._test_buckets[affinity][test] = test_config
       except KeyError:
         logging.exception(
             'Test config for %s is bad.\n Config:%s', test, str(test_config))
 
   @staticmethod
   def _GetAllDevices(active_devices, devices_path):
     try:
       if devices_path:
         devices = [device_utils.DeviceUtils(s)
@@ skipping 116 matching lines @@
   # override
   def _RunTest(self, _device, _test):
     raise NotImplementedError
 
 
 class TestDictVersionError(Exception):
   pass
 
 class PerfTestRunGetStepsError(Exception):
   pass