MDL-31785 import HTMLPurifier 4.4.0+

Includes one extra fix for _blank 8c9d461a6259d7b8ac4ae5c9c9e95ab176cfcda3 compared to 4.4.0 release.

lib/htmlpurifier/HTMLPurifier/AttrDef/HTML/ID.php

@@ -12,12 +12,22 @@
 class HTMLPurifier_AttrDef_HTML_ID extends HTMLPurifier_AttrDef
 {
 
-    // ref functionality disabled, since we also have to verify
-    // whether or not the ID it refers to exists
+    // selector is NOT a valid thing to use for IDREFs, because IDREFs
+    // *must* target IDs that exist, whereas selector #ids do not.
+
+    /**
+     * Determines whether or not we're validating an ID in a CSS
+     * selector context.
+     */
+    protected $selector;
+
+    public function __construct($selector = false) {
+        $this->selector = $selector;
+    }
 
     public function validate($id, $config, $context) {
 
-        if (!$config->get('Attr.EnableID')) return false;
+        if (!$this->selector && !$config->get('Attr.EnableID')) return false;
 
         $id = trim($id); // trim it first
 
@@ -33,10 +43,10 @@ class HTMLPurifier_AttrDef_HTML_ID extends HTMLPurifier_AttrDef
                 '%Attr.IDPrefix is set', E_USER_WARNING);
         }
 
-        //if (!$this->ref) {
+        if (!$this->selector) {
             $id_accumulator =& $context->get('IDAccumulator');
             if (isset($id_accumulator->ids[$id])) return false;
-        //}
+        }
 
         // we purposely avoid using regex, hopefully this is faster
 
@@ -56,7 +66,7 @@ class HTMLPurifier_AttrDef_HTML_ID extends HTMLPurifier_AttrDef
             return false;
         }
 
-        if (/*!$this->ref && */$result) $id_accumulator->add($id);
+        if (!$this->selector && $result) $id_accumulator->add($id);
 
         // if no change was made to the ID, return the result
         // else, return the new id if stripping whitespace made it