Bugzilla

Ah. For posterity and anyone else running afoul of `test_fog_background_update_ping`: the reason the test won't run for me locally is because there is no Background Update on Linux (the platform I was trying to run the test on) (yet) and the test's `skip-if` isn't respected when you run the test directly on the command-line. (Which I already knew and [wrote docs about](https://firefox-source-docs.mozilla.org/toolkit/components/glean/dev/testing.html#integration-marionette-borrowing-telemetry-tests-client-treeherder-symbol-tt-c))

Ah. For posterity and anyone else running afoul of `test_fog_background_update_ping`: the reason the test won't run for me locally is because there is no Background Update on Linux (the platform I was trying to run the test on) (yet) and the test's `skip-if` isn't respected when you run the test directly on the command-line. (Which I already knew and [wrote docs about](https://firefox-source-docs.mozilla.org/toolkit/components/glean/dev/testing.html#integration-marionette-borrowing-telemetry-tests-client-treeherder-symbol-tt-c))

Also, the try run with logs confirms that the ping being sent successfully contains absolutely everything _but_ `uuid.background_update.client_id`:
```json
{
    "ping_info": {
        "seq": 0,
        "start_time": "2021-09-09T14:02+00:00",
        "end_time": "2021-09-09T14:02+00:00"
    },
    "client_info": {
        "telemetry_sdk_build": "40.1.0",
        "first_run_date": "2021-09-09+00:00",
        "architecture": "x86",
        "os_version": "10.0",
        "os": "Windows",
        "app_build": "20210909133459",
        "app_channel": "default",
        "app_display_version": "94.0a1"
    },
    "metrics": {
        "string_list": {
            "background_update.reasons": ["app.update.auto=false", "app.update.background.enabled=false"],
            "background_update.states": ["NEVER_CHECKED"]
        },
        "string": {
            "background_update.final_state": "NEVER_CHECKED",
            "update.channel": "default"
        },
        "boolean": {
            "update.background_update": false,
            "update.auto_download": false,
            "update.can_usually_apply_updates": true,
            "update.can_usually_use_bits": true,
            "update.can_usually_stage_updates": true,
            "update.enabled": true,
            "update.service_enabled": true,
            "update.can_usually_check_for_updates": true,
            "background_update.exit_code_success": true
        }
    }
}
```
Next step: get this running and failing locally on my Windows machine so I can add more logs and poke around why there is no `client_id`. My read of the relevant code suggests that the client_id _must_ be set or else an error would log or there'd be no ping sent at all... so there's something going on here. Maybe we're trying to send an unparseable uuid (but only when delaying ping-lifetime io? Whut.) so it fails silently, or maybe something else is going on.