kernel -> ssa: implement literal lists

pkg/compiler/lib/src/ssa/kernel_ast_adapter.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.
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../common.dart';
 import '../compiler.dart';
 import '../constants/values.dart';
 import '../dart_types.dart';
@@ skipping 127 matching lines @@
   TypeMask selectorTypeOf(ir.MethodInvocation invocation) {
     return TypeMaskFactory.inferredTypeForSelector(
         getSelector(invocation), typeOfInvocation(invocation), _compiler);
   }
 
   TypeMask selectorGetterTypeOf(ir.PropertyGet getter) {
     return TypeMaskFactory.inferredTypeForSelector(
         getGetterSelector(getter), typeOfGet(getter), _compiler);
   }
 
+  ConstantValue getConstantFor(ir.Node node) {
+    ConstantValue constantValue =
+        _backend.constants.getConstantValueForNode(getNode(node), _elements);
+    assert(invariant(getNode(node), constantValue != null,
+        message: 'No constant computed for $node'));
+    return constantValue;
+  }
+
   bool isIntercepted(ir.Node node) {
     Selector selector;
     if (node is ir.PropertyGet) {
       selector = getGetterSelector(node);
     } else {
       selector = getSelector(node);
     }
     return _backend.isInterceptedSelector(selector);
   }
 
@@ skipping 36 matching lines @@
   @override
   DartType visitDynamicType(ir.DynamicType node) {
     return const DynamicType();
   }
 
   @override
   DartType visitInvalidType(ir.InvalidType node) {
     throw new UnimplementedError("Invalid types not currently supported");
   }
 }