Update the plugin API

pkg/analyzer_plugin/test/plugin/fix_mixin_test.dart

 // Copyright (c) 2017, 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 'dart:async';
 
-import 'package:analyzer/dart/analysis/results.dart' hide AnalysisResult;
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/file_system/memory_file_system.dart';
 import 'package:analyzer/src/dart/analysis/driver.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer_plugin/plugin/fix_mixin.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart'
     hide AnalysisError;
 import 'package:analyzer_plugin/protocol/protocol_generated.dart';
+import 'package:analyzer_plugin/src/utilities/fixes/fixes.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 import 'package:path/src/context.dart';
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import 'mocks.dart';
 
 void main() {
   defineReflectiveTests(FixesMixinTest);
 }
@@ skipping 59 matching lines @@
   @override
   List<FixContributor> getFixContributors(AnalysisDriverGeneric driver) {
     return <FixContributor>[
       new _TestFixContributor(<PrioritizedSourceChange>[createChange()]),
       new _TestFixContributor(
           <PrioritizedSourceChange>[createChange(), createChange()])
     ];
   }
 
   @override
-  Future<ResolveResult> getResolveResultForFixes(
-      AnalysisDriverGeneric driver, String path) async {
+  Future<FixesRequest> getFixesRequest(EditGetFixesParams parameters,
+      covariant AnalysisDriverGeneric driver) async {
     AnalysisError error = new AnalysisError(
         new MockSource(), 0, 0, CompileTimeErrorCode.AWAIT_IN_WRONG_CONTEXT);
-    return new AnalysisResult(null, null, null, null, null, null,
-        new LineInfo([0, 20]), null, null, [error], null);
+    AnalysisResult result = new AnalysisResult(null, null, null, null, null,
+        null, new LineInfo([0, 20]), null, null, [error], null);
+    return new FixesRequestImpl(resourceProvider, parameters.offset, result);
   }
 }