context: add missing b prefix
This fixes
mercurial/context.py:593: SyntaxError: cannot mix bytes and nonbytes literals (context.py, line 593)
in Python 3.
--- a/mercurial/context.py Sat Jul 28 16:36:35 2018 +0900
+++ b/mercurial/context.py Mon Jul 30 09:50:32 2018 -0400
@@ -591,7 +591,7 @@
def descendant(self, other):
msg = (b'ctx.descendant(other) is deprecated, '
- 'use ctx.isancestorof(other)')
+ b'use ctx.isancestorof(other)')
self._repo.ui.deprecwarn(msg, b'4.7')
return self.isancestorof(other)