Move exception support to its own library

pkg/analysis_server/lib/src/services/completion/dart/completion_manager.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.
 
 library services.completion.dart.manager;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/protocol/protocol.dart';
 import 'package:analysis_server/src/provisional/completion/completion_core.dart'
     show CompletionContributor, CompletionRequest;
 import 'package:analysis_server/src/provisional/completion/dart/completion_dart.dart';
 import 'package:analysis_server/src/provisional/completion/dart/completion_plugin.dart';
 import 'package:analysis_server/src/provisional/completion/dart/completion_target.dart';
 import 'package:analysis_server/src/services/completion/completion_core.dart';
 import 'package:analysis_server/src/services/completion/completion_performance.dart';
 import 'package:analysis_server/src/services/completion/dart/common_usage_sorter.dart';
 import 'package:analysis_server/src/services/completion/dart/contribution_sorter.dart';
 import 'package:analysis_server/src/services/completion/dart/optype.dart';
 import 'package:analysis_server/src/services/search/search_engine.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
+import 'package:analyzer/exception/exception.dart';
 import 'package:analyzer/file_system/file_system.dart';
 import 'package:analyzer/src/context/context.dart' show AnalysisFutureHelper;
 import 'package:analyzer/src/dart/ast/token.dart';
 import 'package:analyzer/src/generated/engine.dart';
-import 'package:analyzer/src/generated/java_engine.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer/src/task/dart.dart';
 import 'package:analyzer/task/dart.dart';
 import 'package:analyzer/task/model.dart';
 
 /**
  * [DartCompletionManager] determines if a completion request is Dart specific
  * and forwards those requests to all [DartCompletionContributor]s.
  */
 class DartCompletionManager implements CompletionContributor {
@@ skipping 453 matching lines @@
           if (start <= requestOffset && requestOffset <= end) {
             // Replacement range for import URI
             return new ReplacementRange(start, end - start);
           }
         }
       }
     }
     return new ReplacementRange(requestOffset, 0);
   }
 }