Resolve obvious deprecation warnings on bleeding edge

lib/src/closure/closure_annotator.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.
 
-import 'package:analyzer/src/generated/ast.dart' hide ConstantEvaluator;
-import 'package:analyzer/src/generated/element.dart';
+import 'package:analyzer/dart/ast/ast.dart' hide ConstantEvaluator;
+import 'package:analyzer/dart/element/element.dart';
+import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/src/generated/resolver.dart' show TypeProvider;
 
 import '../js/js_ast.dart' as JS show Node, Expression, TypeRef;
 
 import 'closure_annotation.dart';
 
 /// Mixin that can generate [ClosureAnnotation]s for Dart elements and types.
 abstract class ClosureAnnotator {
   TypeProvider get types;
 
@@ skipping 15 matching lines @@
         type: e is VariableElement
             ? emitTypeRef(e.type /*, forceTypeDefExpansion: true*/)
             : null,
         superType: e is ClassElement ? emitTypeRef(e.supertype) : null,
         interfaces:
             e is ClassElement ? e.interfaces.map(emitTypeRef).toList() : null,
         isOverride: e.isOverride,
         isTypedef: e is FunctionTypeAliasElement);
   }
 }