How can offer a copyright assignment? I give permission to do whatever you want with this patch. I don't claim any copyright over it.

On Jan 23 2020, at 5:22 pm, Eli Zaretskii <eliz@gnu.org> wrote:
From: 조성빈 <pcr910303@icloud.com>
Date: Fri, 24 Jan 2020 01:32:21 +0900
Cc: jessenzr@gmail.com

From 1302c040a23837b80a53416421914f3fe8ba1926 Mon Sep 17 00:00:00 2001
From: Sungbin Jo <pcr910303@icloud.com>
Date: Fri, 24 Jan 2020 00:56:38 +0900
Subject: [PATCH] Add new variable for centering lines vertically.

Co-authored-by: Jesse Nazario <jessenzr@gmail.com>

Most of the patch was written by Jesse, and we don't have a copyright
assignment for Jesse on file. We need that to accept this
contribution.

+ if (NILP (BVAR (XBUFFER (it->w->contents),
+ line_spacing_vertical_center)))

No need to use BVAR here, since the buffer whose window is being
displayed is always the current buffer when the display code runs.

Thanks.
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