LibHTML: HtmlView only needs to store the main Frame, not the Document

Remove the Document pointer from HtmlView and always get to it through
the main Frame instead.

The idea here is to move towards HtmlView being higher-level than the
DOM stuff (as much as possible and practical.)

Libraries/LibHTML/HtmlView.cpp

@@ -45,24 +45,25 @@ HtmlView::~HtmlView()
 {
 }
 
-void HtmlView::set_document(Document* document)
+void HtmlView::set_document(Document* new_document)
 {
-    if (document == m_document)
+    RefPtr<Document> old_document = document();
+
+    if (new_document == old_document)
         return;
 
-    if (m_document)
+    if (old_document)
-        m_document->on_layout_updated = nullptr;
+        old_document->on_layout_updated = nullptr;
 
-    m_document = document;
+    main_frame().set_document(new_document);
 
-    if (m_document) {
+    if (new_document) {
-        m_document->on_layout_updated = [this] {
+        new_document->on_layout_updated = [this] {
             layout_and_sync_size();
             update();
         };
     }
 
-    main_frame().set_document(document);
 
 #ifdef HTML_DEBUG
     if (document != nullptr) {
@@ -120,9 +121,9 @@ void HtmlView::paint_event(GPaintEvent& event)
         return;
     }
 
-    painter.fill_rect(event.rect(), m_document->background_color());
+    painter.fill_rect(event.rect(), document()->background_color());
 
-    if (auto background_bitmap = m_document->background_image()) {
+    if (auto background_bitmap = document()->background_image()) {
         painter.draw_tiled_bitmap(event.rect(), *background_bitmap);
     }
 
@@ -142,13 +143,13 @@ void HtmlView::mousemove_event(GMouseEvent& event)
 
     bool hovered_node_changed = false;
     bool is_hovering_link = false;
-    bool was_hovering_link = m_document->hovered_node() && m_document->hovered_node()->is_link();
+    bool was_hovering_link = document()->hovered_node() && document()->hovered_node()->is_link();
     auto result = layout_root()->hit_test(to_content_position(event.position()));
     const HTMLAnchorElement* hovered_link_element = nullptr;
     if (result.layout_node) {
         auto* node = result.layout_node->node();
-        hovered_node_changed = node != m_document->hovered_node();
+        hovered_node_changed = node != document()->hovered_node();
-        m_document->set_hovered_node(const_cast<Node*>(node));
+        document()->set_hovered_node(const_cast<Node*>(node));
         if (node) {
             hovered_link_element = node->enclosing_link_element();
             if (hovered_link_element) {
@@ -163,7 +164,7 @@ void HtmlView::mousemove_event(GMouseEvent& event)
         window()->set_override_cursor(is_hovering_link ? GStandardCursor::Hand : GStandardCursor::None);
     if (hovered_node_changed) {
         update();
-        auto* hovered_html_element = m_document->hovered_node() ? m_document->hovered_node()->enclosing_html_element() : nullptr;
+        auto* hovered_html_element = document()->hovered_node() ? document()->hovered_node()->enclosing_html_element() : nullptr;
         if (hovered_html_element && !hovered_html_element->title().is_null()) {
             auto screen_position = screen_relative_rect().location().translated(event.position());
             GApplication::the().show_tooltip(hovered_html_element->title(), screen_position.translated(4, 4));
@@ -173,7 +174,7 @@ void HtmlView::mousemove_event(GMouseEvent& event)
     }
     if (is_hovering_link != was_hovering_link) {
         if (on_link_hover) {
-            on_link_hover(hovered_link_element ? m_document->complete_url(hovered_link_element->href()).to_string() : String());
+            on_link_hover(hovered_link_element ? document()->complete_url(hovered_link_element->href()).to_string() : String());
         }
     }
     event.accept();
@@ -188,8 +189,8 @@ void HtmlView::mousedown_event(GMouseEvent& event)
     auto result = layout_root()->hit_test(to_content_position(event.position()));
     if (result.layout_node) {
         auto* node = result.layout_node->node();
-        hovered_node_changed = node != m_document->hovered_node();
+        hovered_node_changed = node != document()->hovered_node();
-        m_document->set_hovered_node(const_cast<Node*>(node));
+        document()->set_hovered_node(const_cast<Node*>(node));
         if (node) {
             if (auto* link = node->enclosing_link_element()) {
                 dbg() << "HtmlView: clicking on a link to " << link->href();
@@ -315,8 +316,11 @@ LayoutDocument* HtmlView::layout_root()
 
 void HtmlView::scroll_to_anchor(const StringView& name)
 {
+    if (!document())
+        return;
+
     HTMLAnchorElement* element = nullptr;
-    m_document->for_each_in_subtree([&](auto& node) {
+    document()->for_each_in_subtree([&](auto& node) {
         if (!is<HTMLAnchorElement>(node))
             return;
         auto& anchor_element = to<HTMLAnchorElement>(node);
@@ -336,3 +340,13 @@ void HtmlView::scroll_to_anchor(const StringView& name)
     scroll_into_view({ layout_node.box_type_agnostic_position(), visible_content_rect().size() }, true, true);
     window()->set_override_cursor(GStandardCursor::None);
 }
+
+Document* HtmlView::document()
+{
+    return main_frame().document();
+}
+
+const Document* HtmlView::document() const
+{
+    return main_frame().document();
+}

Libraries/LibHTML/HtmlView.h

@@ -11,8 +11,8 @@ class HtmlView : public GScrollableWidget {
 public:
     virtual ~HtmlView() override;
 
-    Document* document() { return m_document; }
+    Document* document();
-    const Document* document() const { return m_document; }
+    const Document* document() const;
     void set_document(Document*);
 
     const LayoutDocument* layout_root() const;
@@ -49,7 +49,6 @@ private:
     void layout_and_sync_size();
 
     RefPtr<Frame> m_main_frame;
-    RefPtr<Document> m_document;
 
     bool m_should_show_line_box_borders { false };
 };