MDL-80818 QuickForm: Freeze all elements with the same name

There are some radio buttons in activity Completion Conditions settings
that must be frozen altogether, because all of them have the same name.

lib/pear/HTML/QuickForm.php

@@ -1571,15 +1571,16 @@ class HTML_QuickForm extends HTML_Common {
             $elementList = array_flip($elementList);
         }
 
+        $frozen = [];
         foreach (array_keys($this->_elements) as $key) {
             $name = $this->_elements[$key]->getName();
             if ($this->_freezeAll || isset($elementList[$name])) {
                 $this->_elements[$key]->freeze();
-                unset($elementList[$name]);
+                $frozen[$name] = true;
             }
         }
 
-        if (!empty($elementList)) {
+        if (count($elementList) != count($frozen)) {
             return self::raiseError(null, QUICKFORM_NONEXIST_ELEMENT, null, E_USER_WARNING, "Nonexistant element(s): '" . implode("', '", array_keys($elementList)) . "' in HTML_QuickForm::freeze()", 'HTML_QuickForm_Error', true);
         }
         return true;

lib/pear/readme_moodle.txt

@@ -39,6 +39,7 @@ MDL-78145 - PHP 8.2 compliance. Added a missing class property that still need t
             to avoid dynamic properties deprecated error warning.
             And also remove the $_elementIdx because it is not needed in Moodle code.
 MDL-78527 - Adding a sixth parameter to allow groups to use attributes.
+MDL-80818 - Freezing all elements with the same name (e.g. radio buttons)
 
 Pear
 ====