Mark external/wpt/fetch/cross-origin-resource-policy/fetch.https.any.sharedworker.html flaky

Mark the following tests flaky.
- external/wpt/fetch/cross-origin-resource-policy/fetch.https.any.sharedworker.html
- virtual/omt-worker-fetch/external/wpt/fetch/cross-origin-resource-policy/fetch.https.any.sharedworker.html

TBR=creis@chromium.org

BUG: 1012599
Change-Id: I7212bea927e0fbc170e5905cb7bf1f0137c768c3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1855060Reviewed-by: Hayato Ito <hayato@chromium.org>
Commit-Queue: Hayato Ito <hayato@chromium.org>
Cr-Commit-Position: refs/heads/master@{#704970}

third_party/blink/web_tests/TestExpectations

@@ -5791,3 +5791,7 @@ crbug.com/1010593 virtual/disable-deferred-rendering/fast/canvas/canvas-scale-dr
 crbug.com/1010655 virtual/disable-deferred-rendering/fast/canvas/canvas-lost-gpu-context.html [ Failure ]
 crbug.com/1010657 [ Mac ] virtual/disable-deferred-rendering/fast/canvas/image-object-in-canvas.html [ Failure ]
 crbug.com/1011723 virtual/disable-deferred-rendering/fast/canvas/OffscreenCanvas-copyImage.html [ Failure ]
+
+# Sheriff 2019-10-11
+crbug.com/1012599 external/wpt/fetch/cross-origin-resource-policy/fetch.https.any.sharedworker.html [ Pass Timeout ]
+crbug.com/1012599 virtual/outofblink-cors/external/wpt/fetch/cross-origin-resource-policy/fetch.https.any.sharedworker.html [ Pass Timeout ]