[PATCH 11 of 19] amend: use "getcommiteditor()" instead of explicit editor choice

[FUJIWARA Katsunori]

# HG changeset patch
# User FUJIWARA Katsunori <foozy at lares.dti.ne.jp>
# Date 1399736976 -32400
#      Sun May 11 00:49:36 2014 +0900
# Node ID c391c15248f4aa3589753d176702e6b9e1b6cd10
# Parent  04c05644ea80a8547a73523b2384f342801793a7
amend: use "getcommiteditor()" instead of explicit editor choice

This patch doesn't change any tests like as preceding patches, because
editor invocation is already tested in "test-commit-amend.t".

diff --git a/mercurial/cmdutil.py b/mercurial/cmdutil.py
--- a/mercurial/cmdutil.py
+++ b/mercurial/cmdutil.py
@@ -2051,12 +2051,10 @@
 
                 user = opts.get('user') or old.user()
                 date = opts.get('date') or old.date()
-            editor = commiteditor
+            editor = getcommiteditor(**opts)
             if not message:
-                editor = commitforceeditor
+                editor = getcommiteditor(edit=True)
                 message = old.description()
-            elif opts.get('edit'):
-                editor = commitforceeditor
 
             pureextra = extra.copy()
             extra['amend_source'] = old.hex()