This change broke libyuv's presubmit: https://chromium.googlesource.com/chromium/tools/depot_tools/+/e79ddeaabf246769937282f952897bcec3e9de05%5E%21/
GClientKeywords has been removed and replaced with a more direct substitution.
This is similar to https://codereview.webrtc.org/2989603002

BUG=None
NOTRY=True
TBR=fbarchard@google.com

Change-Id: I5cb1c18bc72ac1354d5d69f3c9f93cc61841c409
Reviewed-on: https://chromium-review.googlesource.com/615161Reviewed-by: Henrik Kjellander <kjellander@chromium.org>
Commit-Queue: Henrik Kjellander <kjellander@chromium.org>