repair: use cg3 for treemanifests

The newly created helper changegroup.safeversion() knows to pick
version 03 if the repo uses treemanifests, so just using that means we
pick the right changegroup version.

mercurial/repair.py

@@ -22,9 +22,7 b' from . import ('
 
 def _bundle(repo, bases, heads, node, suffix, compress=True):
     """create a bundle with the specified revisions as a backup"""
-    cgversion = '01'
-    if 'generaldelta' in repo.requirements:
-        cgversion = '02'
+    cgversion = changegroup.safeversion(repo)
 
     cg = changegroup.changegroupsubset(repo, bases, heads, 'strip',
                                        version=cgversion)

tests/test-treemanifest.t

@@ -285,6 +285,17 b' Turning off treemanifest config has no e'
        1       127     111      0       5 25ecb8cb8618 000000000000 000000000000
        2       238      55      1       6 5b16163a30c6 25ecb8cb8618 000000000000
 
+Stripping and recovering changes should work
+
+  $ hg st --change tip
+  M dir1/a
+  $ hg --config extensions.strip= strip tip
+  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
+  saved backup bundle to $TESTTMP/repo-mixed/.hg/strip-backup/51cfd7b1e13b-78a2f3ed-backup.hg (glob)
+  $ hg unbundle -q .hg/strip-backup/*
+  $ hg st --change tip
+  M dir1/a
+
 Create deeper repo with tree manifests.
 
   $ cd ..