LibHTML: Add Comment and CharacterData nodes and improve HTML parsing

This patch adds the CharacterData subclass of Node, which is now the
parent class of Text and a new Comment class.

A Comment node is one of these in HTML: <!--hello friends-->
Since these occur somewhat frequently on the web, we need to be able
to parse them.

This patch also adds a child rejection mechanism to the DOM tree.
Nodes can now override is_child_allowed(Node) and return false if they
don't want a particular Node to become a child of theirs. This is used
to prevent Document from taking on unwanted children.

1 files changed, 2 insertions, 8 deletions

diff --git a/Libraries/LibHTML/DOM/Text.h b/Libraries/LibHTML/DOM/Text.h
index c507dbb3ba..30dd7d02c8 100644
--- a/Libraries/LibHTML/DOM/Text.h
+++ b/Libraries/LibHTML/DOM/Text.h
@@ -1,23 +1,17 @@
 #pragma once
 
 #include <AK/String.h>
-#include <LibHTML/DOM/Node.h>
+#include <LibHTML/DOM/CharacterData.h>
 
-class Text final : public Node {
+class Text final : public CharacterData {
 public:
     explicit Text(Document&, const String&);
     virtual ~Text() override;
 
-    const String& data() const { return m_data; }
-
     virtual String tag_name() const override { return "#text"; }
 
-    virtual String text_content() const override { return m_data; }
-
 private:
     virtual RefPtr<LayoutNode> create_layout_node(const StyleResolver&, const StyleProperties* parent_style) const override;
-
-    String m_data;
 };
 
 template<>