destupdate: indent bookmark and branch logic

We'll move the obsolete related logic first (as it is overwriting any other
anyway) to make the next patch clearer we add indentation in this one.

mercurial/destutil.py

@@ -53,8 +53,9 b' def destupdate(repo, clean=False, check='
     node = None
     wc = repo[None]
     p1 = wc.p1()
-    activemark = None
+    movemark, activemark = None
 
+    if node is None:
     # we also move the active bookmark, if any
     node, movemark = bookmarks.calculateupdate(repo.ui, repo, None)
     if node is not None:
@@ -68,7 +69,6 b' def destupdate(repo, clean=False, check='
                 node = repo.lookup('tip') # update to tip
             else:
                 raise error.Abort(_("branch %s not found") % wc.branch())
-
     if p1.obsolete() and not p1.children():
         # allow updating to successors
         successors = obsolete.successorssets(repo, p1.node())