When outputting a TEXT_RAW node, make sure each child is an instance of DOMCharacterData

Author: downsider

src/HTML5/Serializer/OutputRules.php

@@ -221,7 +221,9 @@ public function element($ele)
         $this->openTag($ele);
         if (Elements::isA($name, Elements::TEXT_RAW)) {
             foreach ($ele->childNodes as $child) {
-                $this->wr($child->data);
+                if ($child instanceof \DOMCharacterData) {
+                    $this->wr($child->data);
+                }
             }
         } else {
             // Handle children.