MDL-55453 core_lib: Fix usage of js_send_uncached

lib/javascript.php

@@ -106,4 +106,4 @@ $content = '';
 foreach ($jsfiles as $jsfile) {
     $content .= file_get_contents($jsfile)."\n";
 }
-js_send_uncached($content, $etag);
+js_send_uncached($content);

lib/requirejs.php

@@ -141,4 +141,4 @@ foreach ($jsfiles as $modulename => $jsfile) {
     $js = implode($replace, explode($search, $js, 2));
     $content .= $js;
 }
-js_send_uncached($content, $etag, 'requirejs.php');
+js_send_uncached($content, 'requirejs.php');