[kernel] Debugging of switch statement

pkg/kernel/lib/clone.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.
 library kernel.clone;
 
 import 'ast.dart';
 import 'type_algebra.dart';
 
 /// Visitor that return a clone of a tree, maintaining references to cloned
 /// objects.
@@ skipping 264 matching lines @@
   }
 
   visitForInStatement(ForInStatement node) {
     var newVariable = clone(node.variable);
     return new ForInStatement(
         newVariable, clone(node.iterable), clone(node.body));
   }
 
   visitSwitchStatement(SwitchStatement node) {
     for (SwitchCase switchCase in node.cases) {
-      switchCases[switchCase] =
-          new SwitchCase(switchCase.expressions.map(clone).toList(), null);
+      switchCases[switchCase] = new SwitchCase(
+          switchCase.expressions.map(clone).toList(),
+          new List<int>.from(switchCase.expressionOffsets),
+          null);
     }
     return new SwitchStatement(
         clone(node.expression), node.cases.map(clone).toList());
   }
 
   visitSwitchCase(SwitchCase node) {
     var switchCase = switchCases[node];
     switchCase.body = clone(node.body)..parent = switchCase;
     return switchCase;
   }
@@ skipping 104 matching lines @@
   visitArguments(Arguments node) {
     return new Arguments(node.positional.map(clone).toList(),
         types: node.types.map(visitType).toList(),
         named: node.named.map(clone).toList());
   }
 
   visitNamedExpression(NamedExpression node) {
     return new NamedExpression(node.name, clone(node.value));
   }
 }