Change ProxyResolutionService API to use std::unique_ptr<Request> instead of raw pointers.

Bug: 479898
Cq-Include-Trybots: luci.chromium.try:linux_mojo
Change-Id: I3d1b89fc33ebae27f6ab4007eceffb9eb6134ef6
Reviewed-on: https://chromium-review.googlesource.com/887598
Commit-Queue: Matt Menke <[email protected]>
Reviewed-by: Steven Bennetts <[email protected]>
Reviewed-by: Bo <[email protected]>
Reviewed-by: Scott Violet <[email protected]>
Reviewed-by: Matt Menke <[email protected]>
Cr-Commit-Position: refs/heads/master@{#578436}
16 files changed