Allow CustomProxyConfig to apply to non-idempotent methods

It is a property of the Data Reduction Proxy that requests using
non-idempotent methods must never be proxied.  Other CustomProxyConfig
providers should be allowed to assume the proxy handles the
non-idempotent case correctly.

Change-Id: I3b31e3c9567e10ccd746541f2f1d46312356f14a
Reviewed-on: https://chromium-review.googlesource.com/c/1385145
Reviewed-by: Eric Roman <eroman@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Commit-Queue: Wojciech Dzier┼╝anowski <wdzierzanowski@opera.com>
Cr-Commit-Position: refs/heads/master@{#626033}
3 files changed