localrepo: do not update bookmarks in addchangegroup We want to update the current bookmark to the most recent revision on current branch unless there is a remote bookmark that points to a different descendant. Addchangegroup is called before we can check for remote bookmarks. We don't update the bookmark in addchangegroup anymore to allow proper updating of bookmarks in pull.

Ancestors of 5
4 2 0 
Ancestors of 6 and 5
3 4 2 1 0 
Ancestors of 5 and 4
4 2 0 

Descendants of 5
7 8 
Descendants of 5 and 3
6 7 8 
Descendants of 5 and 4
5 7 8