1578484 - Refactor raptor browsertime mozproxy implementation

Status: RESOLVED WONTFIX

(Testing :: Raptor, enhancement, P2)

Description

[Robert Wood [:rwood]]

The current implementation of mozproxy playback support in browsertime (landing in Bug 1568048) is sufficient for the first rev of the browsertime mvp, but in the future let's improve this. Noted by nalexander in phab:

I'd like to see it wired into browsertime, but maybe with the existing profile configuration this Just Works. Regardless, I'd like us to push towards the following: browsertime accepts proxy configuration (Desktop and Android) on the command line (--proxy.http{s}=host:port). Therefore, we can push delete_proxy_... down to the Raptor class, since a lot of the profile management pieces don't make sense for browsertime. For browsertime, we want to arrange the Gecko profile with the mitmproxy certs just once, and then use it as a --firefox.profileTemplate directory in each invocation. (In fact that would be cleaner for Raptor: no deleting and re-initializing stuff in an existing profile directory, just copy, modify, repeat.)