rebase: fix bug where --keepbranches could leave wrong branch in dirstate

Report and original fix by Augie Fackler <[e-mail]>

hgext/rebase.py

@@ -172,6 +172,7 b' def concludenode(repo, rev, p1, p2, stat'
                             user=repo[rev].user(),
                             date=repo[rev].date(),
                             extra=extra)
+        repo.dirstate.setbranch(repo[newrev].branch())
         return newrev
     except util.Abort:
         # Invalidate the previous setparents

tests/test-rebase-keep-branch

@@ -28,3 +28,5 b" echo '% Rebase a branch while preserving"
 hg update -C 3
 hg rebase -b 4 -d 3 --keepbranches 2>&1 | sed 's/\(saving bundle to \).*/\1/'
 hg glog --template '{rev}:{desc}:{branches}\n'
+echo '% dirstate branch should be "notdefault"'
+hg branch

tests/test-rebase-keep-branch.out

@@ -31,3 +31,5 b' o 1:c2:'
 |
 o  0:c1:
 
+% dirstate branch should be "notdefault"
+notdefault