LibWeb: Render text inside <input type=password> as asterisks (*)

This makes it possible to enter passwords while recording YouTube
videos. :^)

Userland/Libraries/LibWeb/DOM/Text.h

@@ -31,6 +31,9 @@ public:
 
     WebIDL::ExceptionOr<JS::NonnullGCPtr<Text>> split_text(size_t offset);
 
+    bool is_password_input() const { return m_is_password_input; }
+    void set_is_password_input(Badge<HTML::HTMLInputElement>, bool b) { m_is_password_input = b; }
+
 protected:
     Text(Document&, String const&);
     Text(Document&, NodeType, String const&);
@@ -41,6 +44,7 @@ private:
     JS::GCPtr<HTML::HTMLInputElement> m_owner_input_element;
 
     bool m_always_editable { false };
+    bool m_is_password_input { false };
 };
 
 template<>

Userland/Libraries/LibWeb/HTML/HTMLInputElement.cpp

@@ -344,6 +344,10 @@ void HTMLInputElement::create_shadow_tree_if_needed()
     m_text_node = heap().allocate<DOM::Text>(realm(), document(), initial_value);
     m_text_node->set_always_editable(m_type != TypeAttributeState::FileUpload);
     m_text_node->set_owner_input_element({}, *this);
+
+    if (m_type == TypeAttributeState::Password)
+        m_text_node->set_is_password_input({}, true);
+
     MUST(element->append_child(*m_text_node));
     MUST(shadow_root->append_child(move(element)));
     set_shadow_root(move(shadow_root));

Userland/Libraries/LibWeb/Layout/TextNode.cpp

@@ -35,6 +35,12 @@ static bool is_all_whitespace(StringView string)
 void TextNode::compute_text_for_rendering(bool collapse)
 {
     auto& data = dom_node().data();
+
+    if (dom_node().is_password_input()) {
+        m_text_for_rendering = String::repeated('*', data.length());
+        return;
+    }
+
     if (!collapse || data.is_empty()) {
         m_text_for_rendering = data;
         return;