Index: src/wp-admin/includes/template.php
===================================================================
--- src/wp-admin/includes/template.php	(revision 31869)
+++ src/wp-admin/includes/template.php	(working copy)
@@ -1908,7 +1908,10 @@
 		$attributes = $other_attributes;
 	}
 
-	$button = '<input type="submit" name="' . esc_attr( $name ) . '" id="' . esc_attr( $id ) . '" class="' . esc_attr( $class );
+	// Don't output empty name attributes.
+	$name_attr = $name ? ' name="' . esc_attr( $name ) . '"' : '';
+
+	$button = '<input type="submit"' . $name_attr . ' id="' . esc_attr( $id ) . '" class="' . esc_attr( $class );
 	$button	.= '" value="' . esc_attr( $text ) . '" ' . $attributes . ' />';
 
 	if ( $wrap ) {