rewrite_includes.py: make it work on windows

Also:
    Revert "don't try to format includes on windows"
    This reverts commit e68b5bd4e6e9bdf5a69932fafbd17817572971e4.

Change-Id: I93dc4dba4808c07882e977ac0693c93e282bbad5
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/230878
Commit-Queue: Hal Canary <halcanary@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
2 files changed