[1.6.x] Fixed #23312 -- Marked an i18n test as expectedFailure on Windows/Python 3.

Backport of 433e7dd507 from stable/1.7.x

tests/i18n/commands/extraction.py

@@ -5,6 +5,7 @@ import io
 import os
 import re
 import shutil
+import sys
 import warnings
 
 from django.core import management
@@ -14,7 +15,7 @@ from django.utils._os import upath
 from django.utils import six
 from django.utils.six import StringIO
 from django.utils.translation import TranslatorCommentWarning
-from django.utils.unittest import SkipTest
+from django.utils.unittest import expectedFailure, SkipTest
 
 
 LOCALE='de'
@@ -141,6 +142,10 @@ class BasicExtractorTests(ExtractorTests):
         self.assertIn("UnicodeDecodeError: skipped file not_utf8.txt in .",
                       force_text(stdout.getvalue()))
 
+    # This issue is fixed in 1.8+ (#23312).
+    if six.PY3 and sys.platform.startswith('win'):
+        test_unicode_decode_error = expectedFailure(test_unicode_decode_error)
+
     def test_extraction_warning(self):
         """test xgettext warning about multiple bare interpolation placeholders"""
         os.chdir(self.test_dir)