Remove invalid imports of analysis_server

pkg/analyzer_plugin/lib/src/utilities/completion/element_suggestion_builder.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 'package:analysis_server/src/protocol_server.dart' as protocol;
-import 'package:analysis_server/src/protocol_server.dart'
-    hide Element, ElementKind;
-import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer_plugin/protocol/protocol_common.dart'
+    hide Element, ElementKind;
+import 'package:analyzer_plugin/protocol/protocol_common.dart' as protocol;
 import 'package:analyzer_plugin/src/utilities/completion/suggestion_builder.dart';
+import 'package:analyzer_plugin/utilities/completion/relevance.dart';
 
 /**
  * Common mixin for sharing behavior.
  */
 abstract class ElementSuggestionBuilder {
   // Copied from analysis_server/lib/src/services/completion/dart/suggestion_builder.dart
   /**
    * A collection of completion suggestions.
    */
   final List<CompletionSuggestion> suggestions = <CompletionSuggestion>[];
@@ skipping 83 matching lines @@
           // Cache lone getter/setter so that it can be paired
           _syntheticMap[cacheKey] = suggestion;
         }
       }
       if (_completions.add(suggestion.completion)) {
         suggestions.add(suggestion);
       }
     }
   }
 }