Tamar Christina authored Jan 27, 2016 and Ben Gamari committed Jan 27, 2016

Makes the needed changes to make RemoteGHCi work on Windows.
The approach passes OS Handles areound instead of the Posix Fd
as on Linux.

The reason is that I could not find any real documentation about
the behaviour of Windows w.r.t inheritance and Posix FDs.

The implementation with Fd did not seem to be able to find the Fd
in the child process. Instead I'm using the much better documented
approach of passing inheriting handles.

This requires a small modification to the `process` library.
https://github.com/haskell/process/pull/52

Test Plan: ./validate On Windows x86_64

Reviewers: thomie, erikd, bgamari, simonmar, austin, hvr

Reviewed By: simonmar

Subscribers: #ghc_windows_task_force

Differential Revision: https://phabricator.haskell.org/D1836

GHC Trac Issues: #11100