Auto merge of #20725 - servo-wpt-sync:wpt_update_30-04-2018, r=jdm

Sync WPT with upstream (30-04-2018)

Automated downstream sync of changes from upstream as of 30-04-2018.
[no-wpt-sync]

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1 files changed, 2 insertions, 7 deletions

diff --git a/tests/wpt/web-platform-tests/resources/test/conftest.py b/tests/wpt/web-platform-tests/resources/test/conftest.py
index 0be41eeec54..abc3b6cfdda 100644
--- a/tests/wpt/web-platform-tests/resources/test/conftest.py
+++ b/tests/wpt/web-platform-tests/resources/test/conftest.py
@@ -80,7 +80,7 @@ class HTMLItem(pytest.Item, pytest.Collector):
         if not self.expected:
             assert summarized[u'summarized_status'][u'status_string'] == u'OK', summarized[u'summarized_status'][u'message']
             for test in summarized[u'summarized_tests']:
-                msg = "%s\n%s:\n%s" % (test[u'name'], test[u'message'], test[u'stack'])
+                msg = "%s\n%s" % (test[u'name'], test[u'message'])
                 assert test[u'status_string'] == u'PASS', msg
         else:
             assert summarized == self.expected
@@ -93,12 +93,7 @@ class HTMLItem(pytest.Item, pytest.Collector):
     @staticmethod
     def _scrub_stack(test_obj):
         copy = dict(test_obj)
-
-        assert 'stack' in copy
-
-        if copy['stack'] is not None:
-            copy['stack'] = u'(implementation-defined)'
-
+        del copy['stack']
         return copy
 
     @staticmethod