git-codereview: use fromSlash in TestGofmtSubdir* to make them pass on windows

Change-Id: Ic59299a544d2a8887b305b202c0f5da758ff7322
Reviewed-on: https://go-review.googlesource.com/3071
Reviewed-by: Russ Cox <rsc@golang.org>
2 files changed
tree: 72c2bf85f38715083560cac3066d3164d6e70779
  1. .gitattributes
  2. README
  3. git-codereview/