devtools-frontend is missing from gclient configs, causing the breakage:
https://ci.chromium.org/p/devtools-frontend/builders/ci/DevTools%20Linux/b8904421330390983280

This CL creates the devtools-frontend configuration

R=tandrii@chromium.org
TBR=machenbach@chromium.org
CC=yangguo@chromium.org

Bug: chromium:995657
Change-Id: I8e5ffce16f2b8f69931a71cd67a709427d1f42ab
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/1765591Reviewed-by: Tamer Tas <tmrts@chromium.org>
Auto-Submit: Tamer Tas <tmrts@chromium.org>
Commit-Queue: Tamer Tas <tmrts@chromium.org>