GN: Correct Git Bash removal of leading "/" of "//" labels

Git bash on Windows will remove the leading slash for "//" labels,
changing absolute labels from //foo to /foo. This CL fixes these labels
back to //foo, file system absolute labels are not "fixed".

This modification by Git Bash may be a bug, but looking at the source,
the removal seems to be intentional.

Change-Id: I16d0ca796ce4c1187717f97ab9c3b1c14a6c6a73
Reviewed-on: https://chromium-review.googlesource.com/957084
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Yngve Pettersen <yngve@vivaldi.com>
Cr-Original-Commit-Position: refs/heads/master@{#544203}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 3325da9a7b57fc48650ada6839c74f96d22f3a7c
1 file changed
tree: da0017037ac594d990200652f9fbac9c9e03228a
  1. tools/