for example, in the swarming task's output:

[ RUN      ] TwoClientBookmarksSyncTest.Sanity
[445:775:1107/034546.280272:109465431193:WARNING:loopback_server.cc(633)] Loopback sync persistent state file does not exist.
[445:4099:1107/034546.434224:WARNING:notification_platform_bridge_mac.mm(526)] AlertNotificationService: XPC connection invalidated.
[445:44803:1107/034546.487400:ERROR:service_manager.cc(158)] Connection InterfaceProviderSpec prevented service: content_browser from binding interface: resource_coordinator::mojom::PageSignalGenerator exposed by: resource_coordinator
[445:105999:1107/034548.990824:WARNING:syncer_proto_util.cc(338)] Error posting from syncer: Response Code (bogus on error): -1 Content-Length (bogus on error): -1 Server Status: SYNC_AUTH_ERROR
[445:105999:1107/034548.991770:WARNING:sync_encryption_handler_impl.cc(970)] Nigori had empty encryption keybag.
[445:105999:1107/034548.992172:WARNING:sync_encryption_handler_impl.cc(970)] Nigori had empty encryption keybag.
[445:105999:1107/034549.001292:WARNING:sync_encryption_handler_impl.cc(346)] Ignoring new implicit passphrase. Keystore migration already performed.
[445:115715:1107/034549.047357:WARNING:syncer_proto_util.cc(338)] Error posting from syncer: Response Code (bogus on error): -1 Content-Length (bogus on error): -1 Server Status: SYNC_AUTH_ERROR
[445:115715:1107/034549.053078:WARNING:sync_encryption_handler_impl.cc(346)] Ignoring new implicit passphrase. Keystore migration already performed.
[445:775:1107/034549.770694:ERROR:bookmarks_helper.cc(377)] Title mismatch: Yahoo vs. Google
[445:775:1107/034549.770727:ERROR:bookmarks_helper.cc(415)] Models do not match.
[445:775:1107/034549.770741:ERROR:bookmarks_helper.cc(806)] Model 0 does not match the verifier.
[445:775:1107/034549.776072:ERROR:bookmarks_helper.cc(377)] Title mismatch: Yahoo vs. Google
[445:775:1107/034549.776098:ERROR:bookmarks_helper.cc(415)] Models do not match.
[445:775:1107/034549.776112:ERROR:bookmarks_helper.cc(806)] Model 0 does not match the verifier.
../../chrome/browser/sync/test/integration/bookmarks_helper.cc:92: Failure
Value of: node_->is_favicon_loaded()
  Actual: false
Expected: true
../../chrome/browser/sync/test/integration/bookmarks_helper.cc:92: Failure
Value of: node_->is_favicon_loaded()
  Actual: false
Expected: true
../../chrome/browser/sync/test/integration/bookmarks_helper.cc:92: Failure
Value of: node_->is_favicon_loaded()
  Actual: false
Expected: true
../../chrome/browser/sync/test/integration/bookmarks_helper.cc:92: Failure
Value of: node_->is_favicon_loaded()
  Actual: false
Expected: true

This may be useful to surface somewhere on the page, likely as a link somewhere

Per discussion instead of just surfacing a link we will make a popover UI that extracts the stdio of the swarming output and presents just the relevant subset using some regex matching. This is a new feature, so would make more sense for stable. Moving out of beta.

Per more discussion just links should be fine, as the actual stdio can vary greatly and can lead to more clutter rather than be helpful.