Make server use the common protocol classes

pkg/analysis_server/test/services/correction/organize_directives_test.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.
 
 import 'dart:async';
 
-import 'package:analysis_server/protocol/protocol_generated.dart'
-    hide AnalysisError;
 import 'package:analysis_server/src/services/correction/organize_directives.dart';
 import 'package:analyzer/error/error.dart';
 import 'package:analyzer/src/dart/analysis/driver.dart';
+import 'package:analyzer_plugin/protocol/protocol_common.dart'
+    hide AnalysisError;
 import 'package:test/test.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
 import '../../abstract_single_unit.dart';
 
 main() {
   defineReflectiveSuite(() {
     defineReflectiveTests(OrganizeDirectivesTest);
   });
 }
@@ skipping 309 matching lines @@
     expect(result, expectedCode);
   }
 
   Future<Null> _computeUnitAndErrors(String code) async {
     addTestSource(code);
     AnalysisResult result = await driver.getResult(testSource.fullName);
     testUnit = result.unit;
     testErrors = result.errors;
   }
 }