evolve: handle a case in pubic-div when merging results in same as public In public divergence resolution, what we do is: 1) first apply content divergence resolution 2) then phase divergent resolution on resultant node of 1) case While doing case 1 it is possible that result of merging the two csets would have same changes as public one contains. And then processing the case 2 would create an empty commit which is not something we want to do. So this patch catch that same case when merging results in same as public cset and don't create a new node, instead to solve the divergence it just add a obsmarker from "other divergent" to "public divergent" i.e. [other, (public,)] Next patch will add the continue case handling for this same case. This patch also adds the tests for the different cases which are possible for the above mentioned case. There is test for continue case too which is broken in this patch and will be fixed in next patch.