Only tests under tests/ are run on presubmit, so
presubmit_canned_checks_test.py is not run. Move these there and fix
them.
Bug: 1385693
Change-Id: Ib01a816b0a81919722ea49e5551010251c0e3287
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/4038514
Commit-Queue: Gavin Mak <gavinmak@google.com>
Reviewed-by: Josip Sokcevic <sokcevic@chromium.org>
Reviewed-by: Aravind Vasudevan <aravindvasudev@google.com>