Check for cyclic type variable bounds.

sdk/lib/_internal/compiler/implementation/js_backend/runtime_types.dart

Index: sdk/lib/_internal/compiler/implementation/js_backend/runtime_types.dart
diff --git a/sdk/lib/_internal/compiler/implementation/js_backend/runtime_types.dart b/sdk/lib/_internal/compiler/implementation/js_backend/runtime_types.dart
index d23b1e438cc87a3ecf281c0ed5e76e9877d7d8a7..1d90d6a9a38d452df3b7a34248fb9dcb36c09b74 100644
--- a/sdk/lib/_internal/compiler/implementation/js_backend/runtime_types.dart
+++ b/sdk/lib/_internal/compiler/implementation/js_backend/runtime_types.dart
@@ -465,16 +465,6 @@ class ArgumentCollector extends DartTypeVisitor {
     type.accept(this, false);
   }
 
-  visit(DartType type) {
-    type.accept(this, true);
-  }
-
-  visitList(Link<DartType> types) {
-    for (Link<DartType> link = types; !link.isEmpty; link = link.tail) {
-      link.head.accept(this, true);
-    }
-  }
-
   visitType(DartType type, _) {
     // Do nothing.
   }
@@ -487,13 +477,10 @@ class ArgumentCollector extends DartTypeVisitor {
     if (isTypeArgument) {
       classes.add(type.element);
     }
-    visitList(type.typeArguments);
+    type.visitChildren(this, true);
   }
 
   visitFunctionType(FunctionType type, _) {
-    visit(type.returnType);
-    visitList(type.parameterTypes);
-    visitList(type.optionalParameterTypes);
-    visitList(type.namedParameterTypes);
+    type.visitChildren(this, true);
   }
 }