Re-run `gn help --markdown all > tools/gn/docs/reference.md`.

This should've been part of https://chromium-review.googlesource.com/c/chromium/src/+/1020010

Bug: 835319
Change-Id: Ibad6a9b3f686ed8305ffc77c866917124fef9ba5
Reviewed-on: https://chromium-review.googlesource.com/1021597
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#552387}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: a8fe0c1bdb12ce92c841d4527b54ae3e023cb590
1 file changed
tree: 1cd074f1e92ae415b1662d495e07d7a96357c388
  1. tools/