changegroup: pass 'repo' to allsupportedversions

In the next changesets, we will introduce more logic directly related to the
repository to decide what version have to be supported. So we now directly pass
the repo object instead of just ui.

mercurial/changegroup.py

@@ -874,23 +874,23 b' class cg3packer(cg2packer):'
              '03': (cg3packer, cg3unpacker),
 }
 
-def allsupportedversions(ui):
+def allsupportedversions(repo):
     versions = set(_packermap.keys())
-    if not (ui.configbool('experimental', 'changegroup3') or
-            ui.configbool('experimental', 'treemanifest')):
+    if not (repo.ui.configbool('experimental', 'changegroup3') or
+            repo.ui.configbool('experimental', 'treemanifest')):
         versions.discard('03')
     return versions
 
 # Changegroup versions that can be applied to the repo
 def supportedincomingversions(repo):
-    versions = allsupportedversions(repo.ui)
+    versions = allsupportedversions(repo)
     if 'treemanifest' in repo.requirements:
         versions.add('03')
     return versions
 
 # Changegroup versions that can be created from the repo
 def supportedoutgoingversions(repo):
-    versions = allsupportedversions(repo.ui)
+    versions = allsupportedversions(repo)
     if 'treemanifest' in repo.requirements:
         # Versions 01 and 02 support only flat manifests and it's just too
         # expensive to convert between the flat manifest and tree manifest on