[PATCH 06 of 10 py3] util: use sysstr.join instead of bytes.join in textwrap wrapper

[Augie Fackler]

# HG changeset patch
# User Augie Fackler <raf at durin42.com>
# Date 1495993336 14400
#      Sun May 28 13:42:16 2017 -0400
# Node ID e79e715a5249e5c90c0ef7221253acd2ba69bf12
# Parent  47cbf6238b4a62cead3dc90a4021f7c34ae16f4e
util: use sysstr.join instead of bytes.join in textwrap wrapper

diff --git a/mercurial/util.py b/mercurial/util.py
--- a/mercurial/util.py
+++ b/mercurial/util.py
@@ -2338,7 +2338,7 @@ def MBTextWrapper(**kwargs):
                 # Convert current line back to a string and store it in list
                 # of all lines (return value).
                 if cur_line:
-                    lines.append(indent + ''.join(cur_line))
+                    lines.append(indent + r''.join(cur_line))
 
             return lines