LibWeb: Report if anything is delaying load event, not the count

Some elements that delay the load event are more complicated than a
simple count will allow for. We'll implement those in a bit!

Userland/Libraries/LibWeb/HTML/Parser/HTMLParser.cpp

@@ -304,9 +304,8 @@ void HTMLParser::the_end()
     });
 
     // 8. Spin the event loop until there is nothing that delays the load event in the Document.
-    // FIXME: Track down all the things that are supposed to delay the load event.
     main_thread_event_loop().spin_until([&] {
-        return m_document->number_of_things_delaying_the_load_event() == 0;
+        return !m_document->anything_is_delaying_the_load_event();
     });
 
     // 9. Queue a global task on the DOM manipulation task source given the Document's relevant global object to run the following steps: