LibWeb: Always call update_style() in update_layout()

If the style is dirty, update_style() may cause layout to become dirty.
Therefore we must always update style when updating layout, to ensure
up-to-date results.

Userland/Libraries/LibWeb/DOM/Document.cpp

@@ -554,6 +554,8 @@ void Document::ensure_layout()
 
 void Document::update_layout()
 {
+    update_style();
+
     if (!m_needs_layout && m_layout_root)
         return;
 
@@ -562,8 +564,6 @@ void Document::update_layout()
 
     auto viewport_rect = browsing_context()->viewport_rect();
 
-    update_style();
-
     if (!m_layout_root) {
         Layout::TreeBuilder tree_builder;
         m_layout_root = static_ptr_cast<Layout::InitialContainingBlock>(tree_builder.build(*this));