filemerge: return whether the file is deleted for nomerge internal tools We're going to support the filemerge code resolving change/delete conflicts in upcoming patches. Some of these resolutions require that the dirstate be modified. Modifying the dirstate directly from in here would be (a) a pretty bad layering violation and (b) wrong because all dirstate removals should happen before adds. So in this and upcoming patches we're instead going to pass whether the file is deleted up to merge.mergestate, then in there figure out what dirstate action needs to be taken.