Make server use the common protocol classes

pkg/analysis_server/test/completion_test_support.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 'dart:collection';
 
-import 'package:analysis_server/protocol/protocol_generated.dart';
+import 'package:analyzer_plugin/protocol/protocol_common.dart';
 import 'package:test/test.dart';
 
 import 'domain_completion_test.dart';
 
 /**
  * A base class for classes containing completion tests.
  */
 class CompletionTestCase extends CompletionDomainHandlerTest {
   static const String CURSOR_MARKER = '!';
 
@@ skipping 175 matching lines @@
         err.write("No results for tests:");
         for (String ch in badResults) {
           err..write(' ')..write(ch);
         }
       }
       throw new StateError(err.toString());
     }
     return tests.values.toList();
   }
 }