LibJS: Keep track of current AST node inside the call stack

Author: https://github.com/boricj
Commit: 6172cb3599
Pull-request: https://github.com/SerenityOS/serenity/pull/5547
Reviewed-by: https://github.com/alimpfard
Reviewed-by: https://github.com/linusg

Userland/Libraries/LibJS/Runtime/VM.h

@@ -56,6 +56,7 @@ struct ScopeFrame {
 };
 
 struct CallFrame {
+    const ASTNode* current_node;
     FlyString function_name;
     Value this_value;
     Vector<Value> arguments;