Use async/await in refactorings.

pkg/analysis_server/lib/src/services/refactoring/inline_local.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.
 
 library services.src.refactoring.inline_local;
 
 import 'dart:async';
 
 import 'package:analysis_server/src/protocol_server.dart' hide Element;
 import 'package:analysis_server/src/services/correction/source_range.dart';
@@ skipping 48 matching lines @@
     return _variableElement.name;
   }
 
   @override
   Future<RefactoringStatus> checkFinalConditions() {
     RefactoringStatus result = new RefactoringStatus();
     return new Future.value(result);
   }
 
   @override
-  Future<RefactoringStatus> checkInitialConditions() {
+  Future<RefactoringStatus> checkInitialConditions() async {
     RefactoringStatus result = new RefactoringStatus();
     // prepare variable
     {
       AstNode offsetNode = new NodeLocator.con1(offset).searchWithin(unit);
       if (offsetNode is SimpleIdentifier) {
         Element element = offsetNode.staticElement;
         if (element is LocalVariableElement) {
           _variableElement = element;
           _variableNode = element.node;
         }
       }
     }
     // validate node declaration
     if (!_isVariableDeclaredInStatement()) {
       result = new RefactoringStatus.fatal(
           'Local variable declaration or reference must be selected '
               'to activate this refactoring.');
       return new Future.value(result);
     }
     // should have initializer at declaration
     if (_variableNode.initializer == null) {
       String message = format(
           "Local variable '{0}' is not initialized at declaration.",
           _variableElement.displayName);
       result =
           new RefactoringStatus.fatal(message, newLocation_fromNode(_variableNode));
       return new Future.value(result);
     }
     // prepare references
-    return searchEngine.searchReferences(_variableElement).then((references) {
-      this._references = references;
-      // should not have assignments
-      for (SearchMatch reference in _references) {
-        if (reference.kind != MatchKind.READ) {
-          String message = format(
-              "Local variable '{0}' is assigned more than once.",
-              [_variableElement.displayName]);
-          return new RefactoringStatus.fatal(
-              message,
-              newLocation_fromMatch(reference));
-        }
+    _references = await searchEngine.searchReferences(_variableElement);
+    // should not have assignments
+    for (SearchMatch reference in _references) {
+      if (reference.kind != MatchKind.READ) {
+        String message = format(
+            "Local variable '{0}' is assigned more than once.",
+            [_variableElement.displayName]);
+        return new RefactoringStatus.fatal(
+            message,
+            newLocation_fromMatch(reference));
       }
-      // done
-      return result;
-    });
+    }
+    // done
+    return result;
   }
 
   @override
   Future<SourceChange> createChange() {
     SourceChange change = new SourceChange(refactoringName);
     // remove declaration
     {
       Statement declarationStatement =
           _variableNode.getAncestor((node) => node is VariableDeclarationStatement);
       SourceRange range = utils.getLinesRangeStatements([declarationStatement]);
@@ skipping 92 matching lines @@
         if (initializerOperator == TokenType.MINUS ||
             initializerOperator == TokenType.MINUS_MINUS) {
           return true;
         }
       }
     }
     // no () is needed
     return false;
   }
 }