Code review comment for lp:~weyrick/bzr/54624-warn-on-large-files

Unfortunately this doesn't work if you specify the file name on the bzr add command, in this case the code path seems to go through mutabletree.py _SmartAddHelper._add_one_and_parent().

Also I think there should be a command line way to force adding large files (although that don't need to be part of this patch).