rollback use of isInternal to ignore frames

Author: Nicolas Laurent

src/main/java/org/truffleruby/language/CallStackManager.java

@@ -228,11 +228,6 @@ public boolean ignoreFrame(Node callNode, RootCallTarget callTarget) {
             }
         }
 
-        if (rootNode != null && rootNode.isInternal() &&
-                !BacktraceFormatter.isCore(context, rootNode.getSourceSection())) {
-            return true;
-        }
-
         return rootNode instanceof InternalRootNode || callNode.getEncapsulatingSourceSection() == null;
 
     }