Privacy: add a postbox that is shown when editing the privacy policy page, and where plugins and core will output suggested content and additional privacy info. First run.

Props melchoyce, azaozz.
See #43620.

git-svn-id: https://develop.svn.wordpress.org/trunk@42980 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/functions.php

@@ -6245,3 +6245,13 @@ function wp_privacy_anonymize_data( $type, $data = '' ) {
 	 */
 	return apply_filters( 'wp_privacy_anonymize_data', $anonymous, $type, $data );
 }
+
+/**
+ * Trigger the check for policy text changes.
+ *
+ * @since 4.9.6
+ * @access private 
+ */
+function _wp_privacy_active_plugins_change() {
+	update_option( '_wp_privacy_text_change_check', 'check' );
+}