Mark foreign-fetch-basics and foreign-fetch-cors tests as slow on windows.

Hopefully these tests are indeed just sometimes extra slow (at least a
6x slowdown). If not I'll have to do more digging to see why they sometimes
timeout.

BUG=678498
BUG=678496

Review-Url: https://codereview.chromium.org/2610923011
Cr-Commit-Position: refs/heads/master@{#442100}

third_party/WebKit/LayoutTests/SlowTests

@@ -392,3 +392,13 @@ crbug.com/660492 [ Linux ] storage/indexeddb/structured-clone.html [ Slow ]
 crbug.com/671158 [ Linux ] imported/wpt/encoding/textdecoder-labels.html [ Slow ]
 crbug.com/671158 [ Linux ] http/tests/streams/writable-streams/write.https.html [ Slow ]
 crbug.com/671158 [ Linux ] virtual/mojo-loading/http/tests/streams/writable-streams/write.https.html [ Slow ]
+
+# Usually plenty fast, but sometimes very slow on windows.
+crbug.com/678498 [ Win ] http/tests/serviceworker/foreign-fetch-cors.html [ Slow ]
+crbug.com/678498 [ Win ] virtual/disable-mojo-service-worker/http/tests/serviceworker/foreign-fetch-cors.html [ Slow ]
+crbug.com/678498 [ Win ] virtual/mojo-loading/http/tests/serviceworker/foreign-fetch-cors.html [ Slow ]
+crbug.com/678498 [ Win ] virtual/service-worker-navigation-preload/http/tests/serviceworker/foreign-fetch-cors.html [ Slow ]
+crbug.com/678496 [ Win ] http/tests/serviceworker/foreign-fetch-basics.html [ Slow ]
+crbug.com/678496 [ Win ] virtual/disable-mojo-service-worker/http/tests/serviceworker/foreign-fetch-basics.html [ Slow ]
+crbug.com/678496 [ Win ] virtual/mojo-loading/http/tests/serviceworker/foreign-fetch-basics.html [ Slow ]
+crbug.com/678496 [ Win ] virtual/service-worker-navigation-preload/http/tests/serviceworker/foreign-fetch-basics.html [ Slow ]

third_party/WebKit/LayoutTests/TestExpectations

@@ -2372,9 +2372,5 @@ crbug.com/678492 http/tests/misc/webtiming-ssl.php [ Failure Pass ]
 crbug.com/678492 virtual/mojo-loading/http/tests/misc/webtiming-ssl.php [ Failure Pass ]
 crbug.com/678493 http/tests/permissions/chromium/test-request-window.html [ Timeout Pass ]
 crbug.com/678493 virtual/mojo-loading/http/tests/permissions/chromium/test-request-window.html [ Timeout Pass ]
-crbug.com/678496 http/tests/serviceworker/foreign-fetch-basics.html [ Timeout Pass ]
-crbug.com/678496 virtual/mojo-loading/http/tests/serviceworker/foreign-fetch-basics.html [ Timeout Pass ]
-crbug.com/678498 http/tests/serviceworker/foreign-fetch-cors.html [ Timeout Pass ]
-crbug.com/678498 virtual/mojo-loading/http/tests/serviceworker/foreign-fetch-cors.html [ Timeout Pass ]
 crbug.com/678499 http/tests/security/contentSecurityPolicy/require-sri-for/require-sri-for-script-preload-allowed.php [ Failure Pass ]
 crbug.com/678499 virtual/mojo-loading/http/tests/security/contentSecurityPolicy/require-sri-for/require-sri-for-script-preload-allowed.php [ Failure Pass ]