LibWeb: Remove some unnecessary casts

Author: https://github.com/kevmeyer
Commit: https://github.com/SerenityOS/serenity/commit/821043d798b
Pull-request: https://github.com/SerenityOS/serenity/pull/2755
Reviewed-by: https://github.com/awesomekling

Libraries/LibWeb/Frame/EventHandler.cpp

@@ -60,14 +60,14 @@ const LayoutDocument* EventHandler::layout_root() const
 {
     if (!m_frame.document())
         return nullptr;
-    return static_cast<LayoutDocument*>(m_frame.document()->layout_node());
+    return m_frame.document()->layout_node();
 }
 
 LayoutDocument* EventHandler::layout_root()
 {
     if (!m_frame.document())
         return nullptr;
-    return const_cast<LayoutDocument*>(m_frame.document()->layout_node());
+    return m_frame.document()->layout_node();
 }
 
 bool EventHandler::handle_mouseup(const Gfx::IntPoint& position, unsigned button, unsigned modifiers)