rebase: use obsolete.isenabled() to check for experimental.allowdivergence

Now that obsolete.isenabled() can also check if divergence is allowed, let's
use it for consistency. Other experimental.evolution options are already
checked via this function.

Differential Revision: https://phab.mercurial-scm.org/D11221

hgext/rebase.py

@@ -362,10 +362,7 b' class rebaseruntime(object):'
         skippedset = set(self.obsolete_with_successor_in_destination)
         skippedset.update(self.obsolete_with_successor_in_rebase_set)
         _checkobsrebase(self.repo, self.ui, obsoleteset, skippedset)
-        allowdivergence = self.ui.configbool(
-            b'experimental', b'evolution.allowdivergence'
-        )
-        if allowdivergence:
+        if obsolete.isenabled(self.repo, obsolete.allowdivergenceopt):
             self.obsolete_with_successor_in_rebase_set = set()
         else:
             for rev in self.repo.revs(
@@ -1652,7 +1649,7 b' def _checkobsrebase(repo, ui, rebaseobsr'
     successors in destination or no non-obsolete successor.
     """
     # Obsolete node with successors not in dest leads to divergence
-    divergenceok = ui.configbool(b'experimental', b'evolution.allowdivergence')
+    divergenceok = obsolete.isenabled(repo, obsolete.allowdivergenceopt)
     divergencebasecandidates = rebaseobsrevs - rebaseobsskipped
 
     if divergencebasecandidates and not divergenceok: