LibHTML: Rename Document::normalize() to fixup() and always do it

Node.normalize() is a standard DOM API that coalesces Text nodes.
To avoid clashing with that, rename it to fixup().

This patch also makes it happen automagically as part of parsing.

Libraries/LibHTML/HtmlView.cpp

@@ -182,7 +182,6 @@ void HtmlView::load(const URL& url)
         }
 
         auto document = parse_html(data, url);
-        document->normalize();
 
         set_document(document);