Update the layout test filter to remove bug 673742 as it has been fixed.

third_party/WebKit/LayoutTests/FlagExpectations/enable-browser-side-navigation

 # These tests currently fail when run with --enable-browser-side-navigation
 # See https://crbug.com/576261
 # https://crbug.com/608372: PlzNavigate: support POST navigations
 #  Layout test does not end for unknown reasons.
 crbug.com/608372 http/tests/history/back-to-post.html [ Timeout ]
 crbug.com/608372 virtual/mojo-loading/http/tests/history/back-to-post.html [ Timeout ]
 
 # https://crbug.com/551000: PlzNavigate: DevTools support
 crbug.com/551000 http/tests/inspector/network/x-frame-options-deny.html [ Failure ]
 crbug.com/551000 virtual/mojo-loading/http/tests/inspector/network/x-frame-options-deny.html [ Failure ]
@@ skipping 37 matching lines @@
 # WebFrameClient::didStartProvisionalLoad() and
 # WebFrameClient::didFinishDocumentLoad().
 crbug.com/638900 http/tests/loading/doc-write-sync-third-party-script-reload.html [ Failure ]
 crbug.com/638900 virtual/mojo-loading/http/tests/loading/doc-write-sync-third-party-script-reload.html [ Failure ]
 
 # https://crbug.com/647698: Failing due to absence of call to
 # WebFrameClient::didReceiveServerRedirectForProvisionalLoad.
 crbug.com/647698 http/tests/loading/307-after-303-after-post.html [ Failure ]
 crbug.com/647698 virtual/mojo-loading/http/tests/loading/307-after-303-after-post.html [ Failure ]
 
-# https://crbug.com/673742 Calling document.open should cancel a load
-crbug.com/673742 fast/dom/Document/open-with-pending-load.html [ Failure ]
-
 # Issue with ServiceWorker timing.
 Bug(none) external/wpt/service-workers/service-worker/navigate-window.https.html [ Failure ]
 
 # https://crbug.com/689153: Timeout when receiving a 204 response
 crbug.com/689153 http/tests/navigation/response204.html [ Timeout ]
 crbug.com/689153 virtual/stable/http/tests/navigation/response204.html [ Timeout ]
 crbug.com/689153 virtual/mojo-loading/http/tests/navigation/response204.html [ Timeout ]
 
 # Missing console warning about usage of legacy protocol.
 Bug(none) external/wpt/html/browsers/history/the-location-interface/location-protocol-setter-non-broken-weird.html [ Failure ]
 
 # Missing error messages.
 Bug(none) external/wpt/html/browsers/history/the-location-interface/location-protocol-setter-non-broken.html [ Failure ]
 
 # Missing console error line number.
 Bug(none) http/tests/security/location-href-clears-username-password.html [ Failure ]
 Bug(none) virtual/mojo-loading/http/tests/security/location-href-clears-username-password.html [ Failure ]
 
 # New untriaged.
 Bug(none) http/tests/navigation/back-to-dynamic-iframe.html [ Failure ]
 Bug(none) virtual/mojo-loading/http/tests/navigation/back-to-dynamic-iframe.html [ Failure ]
 
 # This test seems to be partially failing without PlzNavigate as well.
 
 # These tests are flaky.
 Bug(none) http/tests/misc/window-open-then-write.html [ Timeout ]
 Bug(none) external/wpt/html/browsers/browsing-the-web/unloading-documents/beforeunload-on-history-back.html [ Failure ]
 Bug(none) virtual/mojo-loading/http/tests/misc/window-open-then-write.html [ Timeout ]