Make Error.prototype.toString spec compliant; and fix various side-effect-free error printing metho…

src/messages.h

Index: src/messages.h
diff --git a/src/messages.h b/src/messages.h
index 2f48c1020958ead7382190d8098e9586cbe1ce58..b98d1a87d6c95d30692175ebadd423baab35a315 100644
--- a/src/messages.h
+++ b/src/messages.h
@@ -484,44 +484,6 @@ class MessageHandler {
 };
 
 
-class ErrorToStringHelper {
- public:
-  ErrorToStringHelper() : visited_(0) {}
-
-  MUST_USE_RESULT MaybeHandle<String> Stringify(Isolate* isolate,
-                                                Handle<JSObject> error);
-
- private:
-  class VisitedScope {
-   public:
-    VisitedScope(ErrorToStringHelper* helper, Handle<JSObject> error)
-        : helper_(helper), has_visited_(false) {
-      for (const Handle<JSObject>& visited : helper->visited_) {
-        if (visited.is_identical_to(error)) {
-          has_visited_ = true;
-          break;
-        }
-      }
-      helper->visited_.Add(error);
-    }
-    ~VisitedScope() { helper_->visited_.RemoveLast(); }
-    bool has_visited() { return has_visited_; }
-
-   private:
-    ErrorToStringHelper* helper_;
-    bool has_visited_;
-  };
-
-  static bool ShadowsInternalError(Isolate* isolate,
-                                   LookupIterator* property_lookup,
-                                   LookupIterator* internal_error_lookup);
-
-  static MUST_USE_RESULT MaybeHandle<String> GetStringifiedProperty(
-      Isolate* isolate, LookupIterator* property_lookup,
-      Handle<String> default_value);
-
-  List<Handle<JSObject> > visited_;
-};
 }  // namespace internal
 }  // namespace v8