Text widget: bump the TinyMCE modals z-index to 500001 so they show in the Customizer.

Props greuben.
Fixes #41158 for trunk.

git-svn-id: https://develop.svn.wordpress.org/trunk@40990 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/js/widgets/text-widgets.js

@@ -121,6 +121,9 @@ wp.textWidgets = ( function( $ ) {
 					wp.editor.remove( id );
 				}
 
+				// Adjust z-index for the customizer.
+				window.tinymce.ui.FloatPanel.zIndex = 500001;
+
 				wp.editor.initialize( id, {
 					tinymce: {
 						wpautop: true

src/wp-includes/js/tinymce/plugins/wordpress/plugin.js

@@ -1,7 +1,9 @@
 /* global getUserSetting, setUserSetting */
 ( function( tinymce ) {
 // Set the minimum value for the modals z-index higher than #wpadminbar (100000)
-tinymce.ui.FloatPanel.zIndex = 100100;
+if ( tinymce.ui.FloatPanel.zIndex < 100100 ) {
+	tinymce.ui.FloatPanel.zIndex = 100100;
+}
 
 tinymce.PluginManager.add( 'wordpress', function( editor ) {
 	var wpAdvButton, style,