Converted Observatory code-ref function-ref element

runtime/observatory/lib/src/models/objects/code.dart

+// Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file
+
+part of models;
+
+enum CodeKind {
+  dart,
+  native,
+  stub,
+  tag,
+  collected
+}
+
+bool isSyntheticCode(CodeKind kind) {
+  switch (kind) {
+    case CodeKind.collected:
+    case CodeKind.native:
+    case CodeKind.tag:
+      return true;
+    default:
+      return false;
+  }
+}
+
+bool isDartCode(CodeKind kind) => !isSyntheticCode(kind);
+
+abstract class CodeRef extends ObjectRef {
+  /// The name of this class.
+  String get name;
+
+  // What kind of code object is this?
+  CodeKind get kind;
+
+  bool get isOptimized;
+}
+
+abstract class Code extends Object implements CodeRef {
+}