Reenable RTCDataChannel-close

The fix for the timeout has been merged downstream (in webrtc).

Bug: chromium:1087588
Change-Id: Ib22f35cd9b8c7822c079829261685d27f43ba3a7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2228489Reviewed-by: Guido Urdaneta <guidou@chromium.org>
Commit-Queue: Harald Alvestrand <hta@chromium.org>
Cr-Commit-Position: refs/heads/master@{#774529}

third_party/blink/web_tests/TestExpectations

@@ -2664,9 +2664,6 @@ crbug.com/626703 [ Mac ] external/wpt/webtransport/quic/client-indication.sub.an
 crbug.com/626703 [ Win ] external/wpt/webtransport/quic/client-indication.sub.any.html [ Timeout ]
 crbug.com/626703 [ Mac10.14 ] external/wpt/html/browsers/the-window-object/apis-for-creating-and-navigating-browsing-contexts-by-name/open-features-tokenization-screenx-screeny.html [ Timeout ]
 crbug.com/626703 [ Mac10.15 ] external/wpt/html/browsers/the-window-object/apis-for-creating-and-navigating-browsing-contexts-by-name/open-features-tokenization-innerheight-innerwidth.html [ Timeout ]
-crbug.com/626703 [ Linux ] external/wpt/webrtc/RTCDataChannel-close.html [ Timeout ]
-crbug.com/626703 [ Mac ] external/wpt/webrtc/RTCDataChannel-close.html [ Timeout ]
-crbug.com/626703 [ Win ] external/wpt/webrtc/RTCDataChannel-close.html [ Timeout ]
 crbug.com/626703 [ Mac10.15 ] external/wpt/webaudio/the-audio-api/the-mediastreamaudiosourcenode-interface/mediastreamaudiosourcenode-routing.html [ Timeout ]
 crbug.com/626703 [ Mac10.10 ] wpt_internal/display-lock/css-content-visibility/content-visibility-061.html [ Failure Timeout ]
 crbug.com/626703 [ Mac10.10 ] wpt_internal/storage/estimate-usage-details-filesystem.https.tentative.any.worker.html [ Timeout ]