templatefilters: convert arguments to sysstrs for unicode() ctor

Differential Revision: https://phab.mercurial-scm.org/D2538

mercurial/templatefilters.py

@@ -273,7 +273,7 b' def obfuscate(text):'
     """Any text. Returns the input text rendered as a sequence of
     XML entities.
     """
-    text = unicode(text, encoding.encoding, 'replace')
+    text = unicode(text, pycompat.sysstr(encoding.encoding), r'replace')
     return ''.join(['&#%d;' % ord(c) for c in text])
 
 @templatefilter('permissions')