The presubmit system still supports invoking PRESUBMIT.py files using
Python 2. This has recently been turned off on the bots so this change
removes support more completely.
There are still some python3 parameters being passed around - it seemed
better to do the simplest possible removal now, with a follow-up change
to remove more support code after this has sat for a while.
Tests run from PRESUBMIT.py files could still be run using Python 2, but
those should also have been addressed already. Removing support for that
will be done in a subsequent change.
Bug: 1207012
Change-Id: Id244d547a04438f83734dba269c3cc180c148b37
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/4315183
Reviewed-by: Aravind Vasudevan <aravindvasudev@google.com>
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>
