contrib/benchmarks/perf.py

context: switch ctx() use to changectx()

I added `ctx()` to `overlayworkingfilectx`, (and before that, `absentfilectx`),
because `absentfilectx` had reference to this function in its `cmp()` function.

But the standard is actually `changectx()`, and no other class implements
`ctx()`. So let's use the standard name.

(As a result, I'm not sure that part of the `absentfilectx` comparator ever
worked! It was written before I added either function.)

This will be necessary in the next patch.

Differential Revision: https://phab.mercurial-scm.org/D1211

# perf.py - asv benchmarks using contrib/perf.py extension
#
# Copyright 2016 Logilab SA <[e-mail]>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

from . import perfbench

@perfbench()
def track_tags(perf):
    return perf("perftags")

@perfbench()
def track_status(perf):
    return perf("perfstatus", unknown=False)

@perfbench(params=[('rev', ['1000', '10000', 'tip'])])
def track_manifest(perf, rev):
    return perf("perfmanifest", rev)

@perfbench()
def track_heads(perf):
    return perf("perfheads")