dart2dart: Implementation of simple try/catch.

pkg/compiler/lib/src/js_backend/codegen/codegen.dart

 // Copyright (c) 2014, 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 code_generator;
 
 import 'glue.dart';
 
 import '../../tree_ir/tree_ir_nodes.dart' as tree_ir;
 import '../../js/js.dart' as js;
@@ skipping 471 matching lines @@
     accumulator.add(
         buildWhile(new js.LiteralBool(true), node.body, node.label, node));
   }
 
   @override
   void visitReturn(tree_ir.Return node) {
     accumulator.add(new js.Return(visitExpression(node.value)));
   }
 
   @override
+  void visitTryStatement(tree_ir.TryStatement node) {
+    // TODO(kmillikin): implement TryStatement.
+    return giveup(node);
+  }
+
+  @override
   js.Expression visitFieldInitializer(tree_ir.FieldInitializer node) {
     return giveup(node);
     // TODO: implement FieldInitializer
   }
 
   @override
   js.Expression visitSuperInitializer(tree_ir.SuperInitializer node) {
     return giveup(node);
     // TODO: implement SuperInitializer
   }
@@ skipping 21 matching lines @@
   void visitSetField(tree_ir.SetField node) {
     js.PropertyAccess field =
         new js.PropertyAccess.field(
             visitExpression(node.object),
             glue.instanceFieldPropertyName(node.field));
     js.Assignment asn = new js.Assignment(field, visitExpression(node.value));
     accumulator.add(new js.ExpressionStatement(asn));
     visitStatement(node.next);
   }
 }