MDL-55567 messages: Use FORMAT_MOODLE as default for sending messages

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other special features.

lib/externallib.php

@@ -815,11 +815,14 @@ class external_format_value extends external_value {
      *
      * @param string $textfieldname Name of the text field
      * @param int $required if VALUE_REQUIRED then set standard default FORMAT_HTML
+     * @param int $default Default value.
      * @since Moodle 2.3
      */
-    public function __construct($textfieldname, $required = VALUE_REQUIRED) {
+    public function __construct($textfieldname, $required = VALUE_REQUIRED, $default = null) {
 
-        $default = ($required == VALUE_DEFAULT) ? FORMAT_HTML : null;
+        if ($default == null && $required == VALUE_DEFAULT) {
+            $default = FORMAT_HTML;
+        }
 
         $desc = $textfieldname . ' format (' . FORMAT_HTML . ' = HTML, '
                 . FORMAT_MOODLE . ' = MOODLE, '

message/externallib.php

@@ -52,7 +52,7 @@ class core_message_external extends external_api {
                         array(
                             'touserid' => new external_value(PARAM_INT, 'id of the user to send the private message'),
                             'text' => new external_value(PARAM_RAW, 'the text of the message'),
-                            'textformat' => new external_format_value('text', VALUE_DEFAULT),
+                            'textformat' => new external_format_value('text', VALUE_DEFAULT, FORMAT_MOODLE),
                             'clientmsgid' => new external_value(PARAM_ALPHANUMEXT, 'your own client id for the message. If this id is provided, the fail message id will be returned to you', VALUE_OPTIONAL),
                         )
                     )