While implementing bug 1303333, we found that one-off searches originating from about:home or about:newtab are not being counted in UITelemetry. The SEARCH_COUNT histogram looks correct, meaning the the search itself is counted in general. But it doesn't get it counted in UITelemetry / countableevents / search-oneoff. STR: - browse to "about:home" - type something in the search bar at the center of about:home - wait for the one-off engine list to pop up and click on an engine - open "about:telemetry" and select "Raw JSON" - the search will not show in UITelemetry / countableevents / search-oneoff.

This patch should also address the comments from :mak in bug 1303333 comment 24 and bug 1303333 comment 25: - We should add "abouthome" and "newtab" to KNOWN_ONEOFF_SOURCES in BrowserUsageTelemetry.jsm. - We don't have a way to get suggestion/one-off data until this bug is fixed. For this reason, the one-off searches counted in bug 1303333 get into the "search_enter" key. Once we fix this bug, we should make sure to no longer count one-offs in "search_enter" and to add proper test coverage for that case.

Mass wontfix for bugs affecting firefox 52.

Moving to p3 because no activity for at least 1 year(s). See https://github.com/mozilla/bug-handling/blob/master/policy/triage-bugzilla.md#how-do-you-triage for more information

UITelemetry and countableevents no longer exist, so I believe this is no longer valid.