shelve: make non bare shelve not saving branch information in bundle

This patch prepares for restoring newly created branch only on
bare shelve later because information about new-branch will be
preserved only when shelve was bare and working copy branch
was different than branch of its parent. In other case information
about new-branch will be gone, so unshelve will not recognise that
shelve was made on new-branch and it will not restore branch
information from the bundle to the working directory.

hgext/shelve.py

@@ -334,6 +334,11 b' def _docreatecmd(ui, repo, pats, opts):'
                 extra['shelve_unknown'] = '\0'.join(s.unknown)
                 repo[None].add(s.unknown)
 
+        if _iswctxonnewbranch(repo) and not _isbareshelve(pats, opts):
+            # In non-bare shelve we don't store newly created branch
+            # at bundled commit
+            repo.dirstate.setbranch(repo['.'].branch())
+
         def commitfunc(ui, repo, message, match, opts):
             hasmq = util.safehasattr(repo, 'mq')
             if hasmq:
@@ -392,6 +397,9 b' def _isbareshelve(pats, opts):'
             and not opts.get('include', False)
             and not opts.get('exclude', False))
 
+def _iswctxonnewbranch(repo):
+    return repo[None].branch() != repo['.'].branch()
+
 def cleanupcmd(ui, repo):
     """subcommand that deletes all shelves"""