Remove more references to AnalysisContext

pkg/analysis_server/lib/src/services/completion/postfix/postfix_completion.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:analysis_server/src/protocol_server.dart' hide Element;
 import 'package:analysis_server/src/services/correction/util.dart';
 import 'package:analyzer/dart/analysis/session.dart';
 import 'package:analyzer/dart/ast/ast.dart';
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
 import 'package:analyzer/error/error.dart' as engine;
 import 'package:analyzer/src/dart/analysis/driver.dart';
 import 'package:analyzer/src/dart/ast/utilities.dart';
-import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/java_core.dart';
 import 'package:analyzer/src/generated/resolver.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_dart.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
 
 /**
  * An enumeration of possible postfix completion kinds.
  */
 class DartPostfixCompletion {
@@ skipping 245 matching lines @@
 }
 
 /**
  * The computer for Dart postfix completions.
  */
 class PostfixCompletionProcessor {
   static final NO_COMPLETION = new PostfixCompletion(
       DartPostfixCompletion.NO_TEMPLATE, new SourceChange("", edits: []));
 
   final PostfixCompletionContext completionContext;
-  final AnalysisContext analysisContext;
   final CorrectionUtils utils;
   AstNode node;
   PostfixCompletion completion;
   SourceChange change = new SourceChange('postfix-completion');
   final Map<String, LinkedEditGroup> linkedPositionGroups =
       <String, LinkedEditGroup>{};
   Position exitPosition = null;
   TypeProvider _typeProvider;
 
   PostfixCompletionProcessor(this.completionContext)
-      : analysisContext = completionContext.unitElement.context,
-        utils = new CorrectionUtils(completionContext.unit);
+      : utils = new CorrectionUtils(completionContext.unit);
 
   AnalysisDriver get driver => completionContext.driver;
 
   String get eol => utils.endOfLine;
 
   String get file => completionContext.file;
 
   String get key => completionContext.key;
 
   LineInfo get lineInfo => completionContext.lineInfo;
@@ skipping 256 matching lines @@
       [List args]) {
     SourceChange change = builder.sourceChange;
     if (change.edits.isEmpty) {
       completion = null;
       return;
     }
     change.message = formatList(kind.message, args);
     completion = new PostfixCompletion(kind, change);
   }
 }