Cleanup: Presubmit API is built into depot_tools.

Not in gcl, which probably these days nobody working on Chromium uses.

BUG=None
R=maruel@chromium.org
TBR=maruel@chromium.org
NOPRESUBMIT=true

Review URL: https://codereview.chromium.org/887033002

Cr-Commit-Position: refs/heads/master@{#314039}
41 files changed