evolve: use merge.update() for resolving phase divergence Iterating over the manifest when tree manifests and narrowness is in play produces entries for paths outside the narrowspec that represent trees. For example, if the tests/ directory of the hg repo was not in the narrowspec (and the hg repo was using tree manifests, which it doesn't), then there would be a "tests/" entry in the manifest. The merge code deals with some of these cases. For example, it's valid to do a merge if only the local side changes directories outside the narrowspec. That allows rebasing a local commit onto a public commit that had changes to the excluded paths to work. However, _resolvephasedivergent() was iterating of the manifests, which resulted in crashes for some of our users when they tried to resolve phase-divergent commits (actually content-divergent commits that became phase-divergent after the intermediate rebase). We can fix that by relying on merge.update(), since that already handles this case.