The patch in summary is touching both Makefile.in and Makefile.am, probably to avoid autotools rebuild.
This treatment is usually reserved for a few selected system packages that cannot have their autotool scripts rebuilt.
This _could_ cause maintainermode-driven rebuild (see http://blog.flameeyes.eu/articles/2008/06/13/maintaner-mode ), which is something we should be avoiding as much as possible.
Please just patch Makefile.am and/or configure.in/.ac and rebuild autotools, unless you have very good reasons not to.
This is a non-issue and does NOT ever cause a maintainer mode trigger build files rebuild. We are not going to start imposing eautoreconf to everyone.
We did however fix gnome2-utils.eclass gnome2_omf_fix() (called by gnome2_src_unpack) to not sed Makefile.am after Makefile.in but in the proper order (triggers maintainer mode rebuild for all GNOME packages for which the sed changes anything when PORTAGE_TMPDIR is tmpfs with higher accuracy modtime than a second).
Next time actually please provide useful information, so that we wouldn't be looking at the wrong place all along (FILESDIR instead of eclass).