Theme Customizer: Add a Control object to better encapsulate different UI elements and make it easy to switch between hard refreshes and postMessage. see #19910.

git-svn-id: https://develop.svn.wordpress.org/trunk@20128 602fd350-edb4-49c9-b593-d223f7449a82

wp-includes/class-wp-customize-section.php

@@ -72,7 +72,7 @@ class WP_Customize_Section {
 				<?php endif; ?>
 
 				<?php foreach ( $this->settings as $setting ) : ?>
-				<li>
+				<li id="customize-control-<?php echo esc_attr( $setting->id ); ?>" class="customize-control">
 					<?php $setting->_render(); ?>
 				</li>
 				<?php endforeach; ?>