Fix typo in GN's README.md espeially -> especially BUG=None R=brettw@chromium.org,tfarina@chromium.org Review URL: https://codereview.chromium.org/1807983002 Cr-Original-Commit-Position: refs/heads/master@{#381529} Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src Cr-Mirrored-Commit: a46e260bfd246e6523ae5d38047c21441f94e81b