perf: Disable wikipedia stories which are crashing on Windows

TBR=perezju@chromium.org

Bug: 777931
Change-Id: I487a6c7335e310adbf395c51597980f756fef656
Reviewed-on: https://chromium-review.googlesource.com/735546Reviewed-by: Sami Kyöstilä <skyostil@chromium.org>
Commit-Queue: Sami Kyöstilä <skyostil@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511268}

tools/perf/page_sets/system_health/expectations.py

@@ -52,6 +52,10 @@ class SystemHealthDesktopMemoryExpectations(expectations.StoryExpectations):
                       [expectations.ALL], 'crbug.com/769809')
     self.DisableStory('browse:tools:maps', [expectations.ALL_MAC],
                       'crbug.com/773084')
+    self.DisableStory('load:news:wikipedia',
+                      [expectations.ALL_WIN], 'crbug.com/777931')
+    self.DisableStory('load_accessibility:media:wikipedia',
+                      [expectations.ALL_WIN], 'crbug.com/777931')
 
 
 class SystemHealthMobileCommonExpectations(expectations.StoryExpectations):