A PtraceBroker/Client pair implement a PtraceConnection over a socket.
The broker runs in a process with `ptrace` capabilities for the target
process and serves requests for the client over a socket.
Bug: crashpad:30
Change-Id: Ied19bcedf84b46c8f68440fd1c284b2126470e5e
Reviewed-on: https://chromium-review.googlesource.com/780397
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
Reviewed-by: Mark Mentovai <mark@chromium.org>