Make platform-mode default for JUnit tests.

build/android/pylib/junit/test_dispatcher.py

-# Copyright 2014 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.
-
-from pylib import constants
-from pylib.base import base_test_result
-
-def RunTests(tests, runner_factory):
-  """Runs a set of java tests on the host.
-
-  Return:
-    A tuple containing the results & the exit code.
-  """
-  def run(t):
-    runner = runner_factory(None, None)
-    runner.SetUp()
-    results_list, return_code = runner.RunTest(t)
-    runner.TearDown()
-    return (results_list, return_code == 0)
-
-  test_run_results = base_test_result.TestRunResults()
-  exit_code = 0
-  for t in tests:
-    results_list, passed = run(t)
-    test_run_results.AddResults(results_list)
-    if not passed:
-      exit_code = constants.ERROR_EXIT_CODE
-  return (test_run_results, exit_code)
-