Fix tests

lib/src/codegen/nullability_inferrer.dart

 // Copyright (c) 2015, 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 dev_compiler.src.codegen.nullability_inferrer;
 
 import 'package:analyzer/analyzer.dart' hide ConstantEvaluator;
 import 'package:analyzer/src/generated/ast.dart' hide ConstantEvaluator;
 import 'package:analyzer/src/generated/element.dart';
-import 'package:analyzer/src/generated/scanner.dart'
-    show StringToken, Token, TokenType;
+import 'package:analyzer/dart/ast/token.dart' show Token, TokenType;
 
 import 'assignments_index.dart';
 import 'js_codegen.dart' show TemporaryVariableElement;
 import '../utils.dart' show isInlineJS, DirectedGraph;
 
 typedef bool NullableExpressionPredicate(Expression expr);
 
 typedef DartType _StaticTypeGetter(Expression e);
 typedef bool _JSBuiltinTypePredicate(DartType t);
 
@@ skipping 134 matching lines @@
     });
     var nullables = assignmentsGraph.getTransitiveClosure(trivialNullables);
 
     bool isNullableLocal(LocalVariableElement e) {
       // TODO(jmesserly): we should be able to make this work for temps too.
       return e is TemporaryVariableElement || nullables.contains(e);
     }
     return (Expression expr) => _isNullableExpression(expr, isNullableLocal);
   }
 }