LibWeb: Make DOM::Range more suitable for JS.

Author: https://github.com/asynts
Commit: 10f9c85090
Pull-request: https://github.com/SerenityOS/serenity/pull/4318
Reviewed-by: https://github.com/Lubrsi
Reviewed-by: https://github.com/awesomekling
Reviewed-by: https://github.com/linusg

Libraries/LibWeb/Layout/LayoutPosition.cpp

@@ -25,6 +25,7 @@
  */
 
 #include <LibWeb/DOM/Position.h>
+#include <LibWeb/DOM/Range.h>
 #include <LibWeb/Layout/LayoutPosition.h>
 #include <LibWeb/Layout/Node.h>
 
@@ -53,12 +54,14 @@ LayoutRange LayoutRange::normalized() const
     return { m_end, m_start };
 }
 
-DOM::Range LayoutRange::to_dom_range() const
+NonnullRefPtr<DOM::Range> LayoutRange::to_dom_range() const
 {
-    if (!is_valid())
-        return {};
+    ASSERT(is_valid());
 
-    return { m_start.to_dom_position(), m_end.to_dom_position() };
+    auto start = m_start.to_dom_position();
+    auto end = m_end.to_dom_position();
+
+    return DOM::Range::create(*start.node(), start.offset(), *end.node(), end.offset());
 }
 
 }