transaction: remove 'if True:'
This seems to be left over from
96dd93de548c (transaction: reorder
unlinking .hg/journal and .hg/journal.backupfiles, 2015-10-16).
lazymanifest: check more return values in filtercopy
Spotted by Bryan O'Sullivan (and vexingly not the static analyzer I've
been using.)
mercurial: pass ui to extensions.load (
issue5007)
extensions.load does need ui argument to print error if an extension
fails to load.