Removed deprecated $wgDisabledActions

$wgDisabledActions is deprecated since 1.18 and is hardly used
anywhere. It occurs once in includes/DefaultSettings.php where
it is initialized to an empty array.And in Setup.php, for every
action in $wgDisabledActions $wgActions is set to false. Also
added Release notes

Bug: 60460
Change-Id: I5fab95c76b2742b12c1f397d27898148625a9959

RELEASE-NOTES-1.23

@@ -36,6 +36,7 @@ production.
   belongs in LocalSettings.php.
 * $wgSkipSkin, which has been replaceable by $wgSkipSkins since 2005 (r9249), is
   now formally deprecated.
+* Removed deprecated $wgDisabledActions as it is hardly used anywhere.
 
 === New features in 1.23 ===
 * ResourceLoader can utilize the Web Storage API to cache modules client-side.

includes/DefaultSettings.php

@@ -6483,12 +6483,6 @@ $wgActions = array(
 	'watch' => true,
 );
 
-/**
- * Array of disabled article actions, e.g. view, edit, delete, etc.
- * @deprecated since 1.18; just set $wgActions['action'] = false instead
- */
-$wgDisabledActions = array();
-
 /** @} */ # end actions }
 
 /*************************************************************************//**

includes/Setup.php

@@ -341,11 +341,6 @@ if ( !$wgEnotifMinorEdits ) {
 	$wgHiddenPrefs[] = 'enotifminoredits';
 }
 
-# $wgDisabledActions is deprecated as of 1.18
-foreach ( $wgDisabledActions as $action ) {
-	$wgActions[$action] = false;
-}
-
 # We always output HTML5 since 1.22, overriding these is no longer supported
 # we set them here for extensions that depend on its value.
 $wgHtml5 = true;