Parameterize and move JumpTarget/LabelDefition to elements/jumps.dart

pkg/compiler/lib/src/elements/jumps.dart

+// Copyright (c) 2017, 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.
+
+library elements.jumps;
+
+import 'entities.dart';
+
+/// The label entity defined by a labeled statement.
+abstract class LabelDefinition<T> extends Entity {
+  T get label;
+  String get labelName;
+  JumpTarget<T> get target;
+
+  bool get isTarget;
+  bool get isBreakTarget;
+  bool get isContinueTarget;
+
+  void setBreakTarget();
+  void setContinueTarget();
+}
+
+/// A jump target is the reference point of a statement or switch-case,
+/// either by label or as the default target of a break or continue.
+abstract class JumpTarget<T> extends Local {
+  T get statement;
+  int get nestingLevel;
+  List<LabelDefinition<T>> get labels;
+
+  bool get isTarget;
+  bool get isBreakTarget;
+  bool get isContinueTarget;
+  bool get isSwitch;
+
+  // TODO(kasperl): Try to get rid of these.
+  void set isBreakTarget(bool value);
+  void set isContinueTarget(bool value);
+
+  LabelDefinition<T> addLabel(T label, String labelName);
+}