I figured this out. It looks like it was this patch that is causing the conflict:
https://core.trac.www.ads-software.com/attachment/ticket/20533/20533.patch
What fixed it correctly for me was to add the following line to wp-settings.php (just the line, not my “<<<< add this” annotation below):
require( ABSPATH . WPINC . ‘/update.php’ );
require( ABSPATH . WPINC . ‘/canonical.php’ );
require( ABSPATH . WPINC . ‘/shortcodes.php’ );
require( ABSPATH . WPINC . ‘/class-wp-embed.php’ ); <<<< add this
require( ABSPATH . WPINC . ‘/media.php’ );
require( ABSPATH . WPINC . ‘/http.php’ );
require( ABSPATH . WPINC . ‘/class-http.php’ );
For me, this was for an SVN upgrade. If you’re not using SVN, you can manually edit the above file and stop. If you’re using SVN and want more info on how to handle this via SVN, read on.
The bigger issue I figured out is that wp-settings.php had a SVN conflict that never got resolved several updates ago:
$ svn info wp-settings.php
Path: wp-settings.php
Name: wp-settings.php
URL: https://core.svn.www.ads-software.com/tags/3.1.2/wp-settings.php
Repository Root: https://core.svn.www.ads-software.com
Repository UUID: 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Revision: 21100
Node Kind: file
Schedule: normal
Last Changed Author: ryan
Last Changed Rev: 16558
Last Changed Date: 2010-11-23 16:19:38 -0800 (Tue, 23 Nov 2010)
Checksum: 4d75ac52c641f9b5ec7165b700aecc5e
Conflict Previous Base File: wp-settings.php.r15930
Conflict Previous Working File: wp-settings.php.mine
Conflict Current Base File: wp-settings.php.r17841
I don’t use SVN much, so there may be better ways to resolve this, but what I did was:
cp wp-settings.php wp-settings.php.hold
svn remove –force wp-settings.php
svn up wp-settings.php
You can do a “diff -C 5 wp-settings.php.hold wp-settings.php” then to see what the changes were between your version and the repository’s one that you just updated to.