TinyMCE: fix toolbars alignment in RTL.

Fixes #37760 for trunk.
Built from https://develop.svn.wordpress.org/trunk@38349


git-svn-id: http://core.svn.wordpress.org/trunk@38290 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-editor.php

@@ -1259,6 +1259,14 @@ final class _WP_Editors {
 			var init, id, $wrap;
 
 			if ( typeof tinymce !== 'undefined' ) {
+				// Fix RTL
+				tinymce.on( 'addeditor', function( event ) {
+					event.editor.rtl = event.editor.settings.rtl_ui ||
+						( event.editor.editorManager &&
+						event.editor.editorManager.i18n &&
+						event.editor.editorManager.i18n.rtl );
+				}, true );
+
 				for ( id in tinyMCEPreInit.mceInit ) {
 					init = tinyMCEPreInit.mceInit[id];
 					$wrap = tinymce.$( '#wp-' + id + '-wrap' );