WPT import https://crrev.com/c/1214816 introduced new failures in external/wpt/background-fetch:

List of new failures:
external/wpt/background-fetch/idlharness.https.any.html new failing tests: https://crrev.com/c/1214816/4/third_party/WebKit/LayoutTests/external/wpt/background-fetch/idlharness.https.any-expected.txt
external/wpt/background-fetch/idlharness.https.any.serviceworker.html new failing tests: https://crrev.com/c/1214816/4/third_party/WebKit/LayoutTests/external/wpt/background-fetch/idlharness.https.any.serviceworker-expected.txt
external/wpt/background-fetch/idlharness.https.any.worker.html new failing tests: https://crrev.com/c/1214816/4/third_party/WebKit/LayoutTests/external/wpt/background-fetch/idlharness.https.any.worker-expected.txt
external/wpt/background-fetch/idlharness.https.any.sharedworker.html new failing tests: https://crrev.com/c/1214816/4/third_party/WebKit/LayoutTests/external/wpt/background-fetch/idlharness.https.any.sharedworker-expected.txt

This import contains upstream changes from 432d821a4e34012917f2a79306583107b731136e to 530a00d3700d021f1600350736926ea7e4a3cc73:
Update interfaces/cookie-store.idl (#12922): https://github.com/web-platform-tests/wpt/commit/530a00d3700d021f1600350736926ea7e4a3cc73
Update interfaces/cookie-store.idl (#12807): https://github.com/web-platform-tests/wpt/commit/6048455bea40d97c8a5de4c16b7da13c8b455951
Add interfaces/webrtc-dscp.idl (#12806): https://github.com/web-platform-tests/wpt/commit/513b8a03bb9384537529de84172dfa46e1cd0dce
Update interfaces/background-fetch.idl (#12910): https://github.com/web-platform-tests/wpt/commit/19b2ce861d26bbb27f0c0fa3247eacc3d06849a1
Update interfaces/payment-request.idl (#12921): https://github.com/web-platform-tests/wpt/commit/feef356d599379835c25772dbc30837e50f66115
Update interfaces/wasm-js-api.idl (#12920): https://github.com/web-platform-tests/wpt/commit/5d23b640d1921874dbe0d4a8683e52ee49153503
Update interfaces/pointerevents.idl (#12919): https://github.com/web-platform-tests/wpt/commit/3c1bd4dd243b958413d2b4e7a8b45ccb2202b946
Update interfaces/payment-handler.idl (#12917): https://github.com/web-platform-tests/wpt/commit/239b3802a5d1db85097d630996d556413e33ac00
Update interfaces/intersection-observer.idl (#12916): https://github.com/web-platform-tests/wpt/commit/5bcfbf5b53ae3a638ff6f96c3cb75899e20cdfa3