Bug 1720951 - Removed unused 'ensure_bytes()' and 'ensure_unicode()' from runxpcshelltests.py r=mhentges

Since the functions 'ensure_bytes()' and 'ensure_unicode()' were unused, hence removed.

Differential Revision: https://phabricator.services.mozilla.com/D120600

testing/xpcshell/runxpcshelltests.py

@@ -120,18 +120,6 @@ def cleanup_encoding(s):
     return _cleanup_encoding_re.sub(_cleanup_encoding_repl, s)
 
 
-def ensure_bytes(value, encoding="utf-8"):
-    if isinstance(value, six.text_type):
-        return value.encode(encoding)
-    return value
-
-
-def ensure_unicode(value, encoding="utf-8"):
-    if isinstance(value, six.binary_type):
-        return value.decode(encoding)
-    return value
-
-
 """ Control-C handling """
 gotSIGINT = False