Update from https://crrev.com/320343

base/android/jni_generator/jni_generator_tests.py

 #!/usr/bin/env python
 # Copyright (c) 2012 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.
 
 """Tests for jni_generator.py.
 
 This test suite contains various tests for the JNI generator.
 It exercises the low-level parser all the way up to the
 code generator and ensures the output matches a golden
 file.
 """
 
 import difflib
 import inspect
+import optparse
 import os
 import sys
 import unittest
 import jni_generator
 from jni_generator import CalledByNative, JniParams, NativeMethod, Param
 
 
 SCRIPT_NAME = 'base/android/jni_generator/jni_generator.py'
 INCLUDES = (
     'base/android/jni_generator/jni_generator_helper.h'
@@ skipping 1115 matching lines @@
     private static native void nativeDoSomething(Bar1.Callback callback1,
                                                  Bar2.Callback callback2);
     }
     """
     jni_from_java = jni_generator.JNIFromJavaSource(test_data,
                                                     'org/chromium/foo/Foo',
                                                     TestOptions())
     self.assertGoldenTextEquals(jni_from_java.GetContent())
 
 
+def TouchStamp(stamp_path):
+  dir_name = os.path.dirname(stamp_path)
+  if not os.path.isdir(dir_name):
+    os.makedirs()
+
+  with open(stamp_path, 'a'):
+    os.utime(stamp_path, None)
+
+
+def main(argv):
+  parser = optparse.OptionParser()
+  parser.add_option('--stamp', help='Path to touch on success.')
+  options, _ = parser.parse_args(argv[1:])
+
+  test_result = unittest.main(argv=argv[0:1], exit=False)
+
+  if test_result.result.wasSuccessful() and options.stamp:
+    TouchStamp(options.stamp)
+
+  return not test_result.result.wasSuccessful()
+
+
 if __name__ == '__main__':
-  unittest.main()
+  sys.exit(main(sys.argv))