Disable flaky http/tests/media/media-source/mediasource-duration.html on Win

TBR=wolenetz@chromium.org

Bug: 689781
Change-Id: I432995526e5aa0a2e235bf2a8a496ed265cbff74
Reviewed-on: https://chromium-review.googlesource.com/c/1343086
Commit-Queue: Maxim Kolosovskiy <kolos@chromium.org>
Reviewed-by: Maxim Kolosovskiy <kolos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609679}

third_party/WebKit/LayoutTests/TestExpectations

@@ -4121,6 +4121,7 @@ crbug.com/678499 virtual/outofblink-cors-ns/http/tests/security/contentSecurityP
 crbug.com/747751 [ Win ] http/tests/devtools/application-panel/resources-panel-resource-preview.js [ Failure Pass ]
 
 crbug.com/689781 external/wpt/media-source/mediasource-duration.html [ Failure Pass ]
+crbug.com/689781 [ Win ] http/tests/media/media-source/mediasource-duration.html [ Failure Pass ]
 
 crbug.com/681468 fast/forms/suggestion-picker/date-suggestion-picker-appearance-zoom125.html [ Failure Pass ]
 crbug.com/681468 fast/forms/suggestion-picker/date-suggestion-picker-appearance-zoom200.html [ Failure Pass ]