Miscellaneous cleanups to the data reduction proxy

* Remove some of the leftover tamper detection code
* Add an explicit callback when a new client config is fetched
* Limit the use of mock config for only the tests where it is actually required
* Remove the deprecated mock call to the network quality estimator

Bug: 760294, 675761
Change-Id: Iaf8077e83bacca574aa6dea0ed9906f0d25d0176
Reviewed-on: https://chromium-review.googlesource.com/766072
Reviewed-by: Doug Arnett <dougarnett@chromium.org>
Commit-Queue: Tarun Bansal <tbansal@chromium.org>
Cr-Commit-Position: refs/heads/master@{#516088}
9 files changed