templatekw: inline showlist() into showbookmarks()

showlist() is the helper to build _hybrid object from a trivial list. It can't
be applied if each value has more than one items, 'bookmark' and 'current' in
this case.

This change is necessary to fix random failure of "{join(bookmarks, sep)}".

mercurial/templatekw.py

@@ -199,10 +199,10 b' def showbookmarks(**args):'
     """
     repo = args['ctx']._repo
     bookmarks = args['ctx'].bookmarks()
-    hybrid = showlist('bookmark', bookmarks, **args)
-    for value in hybrid.values:
-        value['current'] = repo._bookmarkcurrent
-    return hybrid
+    current = repo._bookmarkcurrent
+    c = [{'bookmark': x, 'current': current} for x in bookmarks]
+    f = _showlist('bookmark', bookmarks, **args)
+    return _hybrid(f, c)
 
 def showchildren(**args):
     """:children: List of strings. The children of the changeset."""