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diff --git a/includes/deferred/DeferredUpdates.php b/includes/deferred/DeferredUpdates.php
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+<?php
+/**
+ * Interface and manager for deferred updates.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * http://www.gnu.org/copyleft/gpl.html
+ *
+ * @file
+ */
+
+/**
+ * Interface that deferrable updates should implement. Basically required so we
+ * can validate input on DeferredUpdates::addUpdate()
+ *
+ * @since 1.19
+ */
+interface DeferrableUpdate {
+	/**
+	 * Perform the actual work
+	 */
+	function doUpdate();
+}
+
+/**
+ * Class for managing the deferred updates.
+ *
+ * @since 1.19
+ */
+class DeferredUpdates {
+	/**
+	 * Store of updates to be deferred until the end of the request.
+	 */
+	private static $updates = array();
+
+	/**
+	 * Add an update to the deferred list
+	 * @param DeferrableUpdate $update Some object that implements doUpdate()
+	 */
+	public static function addUpdate( DeferrableUpdate $update ) {
+		array_push( self::$updates, $update );
+	}
+
+	/**
+	 * HTMLCacheUpdates are the most common deferred update people use. This
+	 * is a shortcut method for that.
+	 * @see HTMLCacheUpdate::__construct()
+	 * @param Title $title
+	 * @param string $table
+	 */
+	public static function addHTMLCacheUpdate( $title, $table ) {
+		self::addUpdate( new HTMLCacheUpdate( $title, $table ) );
+	}
+
+	/**
+	 * Add a callable update.  In a lot of cases, we just need a callback/closure,
+	 * defining a new DeferrableUpdate object is not necessary
+	 * @see MWCallableUpdate::__construct()
+	 * @param callable $callable
+	 */
+	public static function addCallableUpdate( $callable ) {
+		self::addUpdate( new MWCallableUpdate( $callable ) );
+	}
+
+	/**
+	 * Do any deferred updates and clear the list
+	 *
+	 * @param string $commit Set to 'commit' to commit after every update to
+	 *   prevent lock contention
+	 */
+	public static function doUpdates( $commit = '' ) {
+		global $wgDeferredUpdateList;
+
+		wfProfileIn( __METHOD__ );
+
+		$updates = array_merge( $wgDeferredUpdateList, self::$updates );
+
+		// No need to get master connections in case of empty updates array
+		if ( !count( $updates ) ) {
+			wfProfileOut( __METHOD__ );
+
+			return;
+		}
+
+		$dbw = false;
+		$doCommit = $commit == 'commit';
+		if ( $doCommit ) {
+			$dbw = wfGetDB( DB_MASTER );
+		}
+
+		while ( $updates ) {
+			self::clearPendingUpdates();
+
+			/** @var DeferrableUpdate $update */
+			foreach ( $updates as $update ) {
+				try {
+					$update->doUpdate();
+
+					if ( $doCommit && $dbw->trxLevel() ) {
+						$dbw->commit( __METHOD__, 'flush' );
+					}
+				} catch ( MWException $e ) {
+					// We don't want exceptions thrown during deferred updates to
+					// be reported to the user since the output is already sent.
+					// Instead we just log them.
+					if ( !$e instanceof ErrorPageError ) {
+						MWExceptionHandler::logException( $e );
+					}
+				}
+			}
+			$updates = array_merge( $wgDeferredUpdateList, self::$updates );
+		}
+
+		wfProfileOut( __METHOD__ );
+	}
+
+	/**
+	 * Clear all pending updates without performing them. Generally, you don't
+	 * want or need to call this. Unit tests need it though.
+	 */
+	public static function clearPendingUpdates() {
+		global $wgDeferredUpdateList;
+		$wgDeferredUpdateList = self::$updates = array();
+	}
+}