merge: drop commitinfo argument to applyupdates (API) We now pass the mergeresult object and hence there is no need to have a separate commitinfo argument as the required info is present in mergeresult object. Differential Revision: https://phab.mercurial-scm.org/D8904

merge: remove emptyactions() and use collections.defaultdict(list) instead emptyactions() used to return a dict which was populated and passed into applyupdates(). However, with recent changes, we no longer pass a plain dict, instead we pass the mergeresult object. There was only one usage of emptyactions and that too inside mergeresult object. That usage is replaced with collections.defaultdict(list) instead. Not sure why we were not using collections.defaultdict(list) from the beginning. Differential Revision: https://phab.mercurial-scm.org/D8903

merge: pass mergeresult obj in _forgetremoved() (API) Instead of returning a dict of actions and then updating it, let's pass the object directly and update it there. This makes `updateactions()` on mergeresult unused and this patch removes that. After this patch, we have couple of methods left on mergeresult class which still exposes the internal dict based action storage. Differential Revision: https://phab.mercurial-scm.org/D8889