[Android] Split DeviceUtils tests and run them in presubmit.

build/android/PRESUBMIT.py

 # Copyright (c) 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.
 
 """Presubmit script for android buildbot.
 
 See http://dev.chromium.org/developers/how-tos/depottools/presubmit-scripts for
 details on the presubmit API built into gcl.
 """
 
@@ skipping 32 matching lines @@
           J(), J('..', '..', 'third_party', 'android_testrunner'),
           J('buildbot')]))
   output.extend(input_api.canned_checks.RunPylint(
       input_api,
       output_api,
       white_list=[r'gyp/.*\.py$', r'gn/.*\.py'],
       extra_paths_list=[J('gyp'), J('gn')]))
 
   output.extend(input_api.canned_checks.RunUnitTestsInDirectory(
       input_api, output_api, J('buildbot', 'tests')))
+
+  pylib_test_env = dict(input_api.environ)
+  pylib_test_env.update({
+      'PYTHONPATH': input_api.PresubmitLocalPath(),
+      'PYTHONDONTWRITEBYTECODE': '1',
+  })
+  output.extend(input_api.canned_checks.RunUnitTests(

[frankf, 2014/07/10 17:45:09]

Why not run all pylib unit tests on the bots? These tests are likely going to
get larger in the future, not sure it makes sense to run them during presubmit.
I think tools like telemetry run their unittests on the bots, right?

[jbudorick, 2014/07/10 18:08:49]

I think that should be our goal. Even with that, though, I don't particularly
see a problem in running tests that are "fast enough" -- an admittedly slippery
distinction -- in presubmit.

(fwiw, the DeviceUtils tests currently run in ~1/3s, and I don't anticipate them
taking longer than 1s when finished.)

+      input_api,
+      output_api,
+      unit_tests=[
+          J('pylib', 'device', 'device_utils_test.py'),],
+      env=pylib_test_env))
   output.extend(_CheckDeletionsOnlyFiles(input_api, output_api))
   return output
 
 
 def CheckChangeOnUpload(input_api, output_api):
   return CommonChecks(input_api, output_api)
 
 
 def CheckChangeOnCommit(input_api, output_api):
   return CommonChecks(input_api, output_api)