Make JSON validity presubmit test less stringent.

On Mac, Python 2.7 gives different results (line 1 column 3 char 2) than
Python 2.6 (line 1 column 2 char 2).

Review URL: https://codereview.chromium.org/335263002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@277728 0039d316-1c4b-4281-b951-d872f2087c98

PRESUBMIT_test.py

@@ -470,25 +470,26 @@ def testFailure(self):
     test_data = [
       ('invalid_json_1.json',
        ['{ x }'],
-       'Expecting property name: line 1 column 2 (char 2)'),
+       'Expecting property name:'),
       ('invalid_json_2.json',
        ['// Hello world!',
         '{ "hello": "world }'],
-       'Unterminated string starting at: line 2 column 12 (char 12)'),
+       'Unterminated string starting at:'),
       ('invalid_json_3.json',
        ['{ "a": "b", "c": "d", }'],
-       'Expecting property name: line 1 column 22 (char 22)'),
+       'Expecting property name:'),
       ('invalid_json_4.json',
        ['{ "a": "b" "c": "d" }'],
-       'Expecting , delimiter: line 1 column 11 (char 11)'),
+       'Expecting , delimiter:'),
       ]
 
     input_api.files = [MockFile(filename, contents)
                        for (filename, contents, _) in test_data]
 
     for (filename, _, expected_error) in test_data:
       actual_error = PRESUBMIT._GetJSONParseError(input_api, filename)
-      self.assertEqual(expected_error, str(actual_error))
+      self.assertTrue(expected_error in str(actual_error),
+                      "'%s' not found in '%s'" % (expected_error, actual_error))
 
   def testNoEatComments(self):
     input_api = MockInputApi()