A good first bug to test the contribution workflow
http://sylvestre.ledru.info/reports/fx-scan-build/report-TrackUnionStream.cpp-CopyTrackData-24-1.html#EndPath
The line can probably be safely removed

Note that we have (at least) three documentations to start contributing (esp with phabricator):
https://wiki.mozilla.org/Phabricator/FAQ
https://developer.mozilla.org/en-US/docs/Mozilla/Developer_guide/How_to_Submit_a_Patch
https://moz-conduit.readthedocs.io/en/latest/phabricator-user.html

(something that we should improve at some point)

This is a change suggested by static analysis: http://sylvestre.ledru.info/reports/fx-scan-build/report-TrackUnionStream.cpp-CopyTrackData-24-1.html#EndPath

The condition that triggers the line in question breaks out of the loop.

for (some range)
  value = foo

  if (condition) {
    value = bar // the line in question
    break;
  }

  /* use value */

end

So if the condition is triggered, we leave the loop before value is used.

Local build and test confirmed. Requesting landing.

Should be marked as fixed only whem on mc

I used Lando

This is autoland, not mc

https://hg.mozilla.org/mozilla-central/rev/ce681d2ac834