[push-api] Discovering relevant service timers (#111)

@costinm notes that the following might be useful:

>1. for services that store messages for offline devices - how long will
they be stored if the device doesn't connect ( 3 weeks for GCM for example )
>
> 2. how long will the push service keep accepting incoming messages for
devices that have not been seen in a long time.
>
> 3. how long the push service will keep record of a particular device ( for
privacy and storage the service may delete all records associated with such
device )


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Reply to this email directly or view it on GitHub:
https://github.com/w3c/push-api/issues/111