Martin von Zweigbergk <martinvonz@google.com> [Wed, 27 Feb 2019 16:15:10 -0800] rev 41811
absorb: use scmutil.cleanupnodes() so operation gets set
The operation is useful for e.g. `hg obslog` output.
Differential Revision: https://phab.mercurial-scm.org/D6034