Only show 'Preview' on the custom header screen if there is something to show.

props nickmomrik.
fixes #14531.


git-svn-id: https://develop.svn.wordpress.org/trunk@25135 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/custom-header.php

@@ -464,6 +464,7 @@ class Custom_Image_Header {
 <table class="form-table">
 <tbody>
 
+<?php if ( get_custom_header() || display_header_text() ) : ?>
 <tr valign="top">
 <th scope="row"><?php _e( 'Preview' ); ?></th>
 <td>
@@ -490,6 +491,8 @@ class Custom_Image_Header {
 	<?php } ?>
 </td>
 </tr>
+<?php endif; ?>
+
 <?php if ( current_theme_supports( 'custom-header', 'uploads' ) ) : ?>
 <tr valign="top">
 <th scope="row"><?php _e( 'Select Image' ); ?></th>