Hard deprecate BaseTemplate::getFooterIcons()

BaseTemplate::getFooterIcons() is soft deprecated since 1.35 and unused.

Bug: T267447
Change-Id: Iff952cff08a5c93b93ab75743ea6f1e18067572f

RELEASE-NOTES-1.36

@@ -650,6 +650,8 @@ because of Phabricator reports.
   DatabaseBlock::isExemptedFromAutoblocks instead.
 * User::isIPRange(), deprecated in 1.35, is hard deprecated.
   Use the UserNameUtils service or IPUtils directly.
+* BaseTemplate::getFooterIcons(), deprecated in 1.35, is hard deprecated. Read
+  footer icons from template data requested via $this->get('footericons').
 * …
 
 === Other changes in 1.36 ===

includes/skins/BaseTemplate.php

@@ -327,6 +327,7 @@ abstract class BaseTemplate extends QuickTemplate {
 	 * @return array
 	 */
 	protected function getFooterIcons( $option = null ) {
+		wfDeprecated( __METHOD__, '1.35' );
 		// Generate additional footer icons
 		$footericons = $this->get( 'footericons' );