Aww… There was some heated discussion on the emacs-devel mailing list about this change… Basically the emacs maintainer thought that this was an unintended feature and made a poll to know whether some packages would break with this change. No convincing examples came up, so he went on with the change.
For your problem, I guess that simply replacing all occurrences of save-excursion with save-excursion-and-mark should work, as an overkill solution.
– Skywalker 2016-01-17 09:51 UTC