Add a networking off-main-thread outcome

[acreskeyMoz]

This outcome examines omt-specific networking performance probes

[acreskeyMoz]

This is my first time making use of glean timing_distributions.
I'm not sure if this is valid

select_expression = '{{agg_histogram_mean("metrics.timing_distribution.http_content_onstart_delay")}}'

[mikewilli]

It looks like you're missing the metrics data_source definition, which is why the validate-jetstream CI check is failing. I also tagged @danielkberry to help with reviewing the metric definitions.

[acreskeyMoz]

Thanks.

I'm looking into some other glam probes and I'm pretty sure that my data extraction isn't correct.
So I'm expecting to need to also update the select_expression.

[mikewilli]

Are we still interested in updating and merging this outcome or can this PR be closed?

[acreskeyMoz]

Oh, no longer needed!