fromupstream: fix 'bug' handling

The introduction of --crbug and --buganizer broke
(a) the BUG= handling in --replace and
(b) the "missing BUG=" detection
because now, args['bug'] will never remain 'None'.

Let's only re-assign args['bug'] if we had 1 or more crbug or buganizer
args.

BUG=none
TEST=`fromupstream.py --replace ...` honors the old BUG= line

Change-Id: I808b28b62f75b85fe11ffeedbc49d6dbf916820c
Reviewed-on: https://chromium-review.googlesource.com/1368184
Commit-Ready: Brian Norris <briannorris@chromium.org>
Tested-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
1 file changed