py3: use bytes instead of str in instance()

We deal internally with bytes, so we should check whether the remote is a bytes
or not.

Differential Revision: https://phab.mercurial-scm.org/D3126

mercurial/logexchange.py

@@ -106,7 +106,7 b' def activepath(repo, remote):'
     rpath = remote
     if local:
         rpath = remote._repo.root
-    elif not isinstance(remote, str):
+    elif not isinstance(remote, bytes):
         rpath = remote._url
 
     # represent the remotepath with user defined path name if exists