Disabling flaky layout tests

virtual/outofblink-cors/external/wpt/service-workers/service-worker/about-blank-replacement.https.html
http/tests/devtools/sources/debugger-breakpoints/event-listener-breakpoints-webaudio.js

TBR=tkent@chromium.org

Bug: 857410, 857414
Change-Id: I422301df885098ca66b440d01b0fc5bd54a4a8a9
Reviewed-on: https://chromium-review.googlesource.com/1118167Reviewed-by: Henrik Grunell <grunell@chromium.org>
Commit-Queue: Henrik Grunell <grunell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#571085}

third_party/WebKit/LayoutTests/TestExpectations

@@ -4731,3 +4731,7 @@ crbug.com/856601 [ Linux ] virtual/feature-policy-permissions/external/wpt/media
 crbug.com/856955 [ Win10 Linux ] inspector-protocol/animation/animation-multiple-frames.js [ Failure Pass ]
 crbug.com/856969 [ Win Linux Mac ] external/wpt/fetch/api/abort/serviceworker-intercepted.https.html [ Pass Timeout ]
 crbug.com/856969 [ Win Linux Mac ] virtual/outofblink-cors/external/wpt/fetch/api/abort/serviceworker-intercepted.https.html [ Pass Timeout ]
+
+# Sheriff 2018-06-28
+crbug.com/857410 [ Linux ] virtual/outofblink-cors/external/wpt/service-workers/service-worker/about-blank-replacement.https.html [ Pass Timeout ]
+crbug.com/857414 [ Win ] http/tests/devtools/sources/debugger-breakpoints/event-listener-breakpoints-webaudio.js [ Pass Timeout ]