Switch server tests to strong mode.

pkg/analysis_server/test/services/refactoring/extract_method_test.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 'package:analysis_server/src/services/correction/status.dart';
 import 'package:analysis_server/src/services/refactoring/extract_method.dart';
 import 'package:analysis_server/src/services/refactoring/refactoring.dart';
 import 'package:analyzer_plugin/protocol/protocol_common.dart';
@@ skipping 876 matching lines @@
     RefactoringStatus status = await refactoring.checkInitialConditions();
     assertRefactoringStatus(status, RefactoringProblemSeverity.FATAL,
         expectedMessage:
             'Cannot extract closure as method, it references 1 external variable(s).');
   }
 
   test_fromTopLevelVariableInitializerClosure() async {
     await indexTestUnit('''
 var X = 1;
 
-var Y = () {
+dynamic Y = () {
   return 1 + X;
 };
 ''');
     _createRefactoringForString('1 + X');
     // apply refactoring
     return _assertSuccessfulRefactoring('''
 var X = 1;
 
-var Y = () {
+dynamic Y = () {
   return res();
 };
 
-num res() => 1 + X;
+int res() => 1 + X;
 ''');
   }
 
   test_getExtractGetter_expression_true_binaryExpression() async {
     await indexTestUnit('''
 main() {
   print(1 + 2);
 }
 ''');
     _createRefactoringForString('1 + 2');
@@ skipping 1912 matching lines @@
    * Returns a deep copy of [refactoring] parameters.
    * There was a bug masked by updating parameter instances shared between the
    * refactoring and the test.
    */
   List<RefactoringMethodParameter> _getParametersCopy() {
     return refactoring.parameters.map((p) {
       return new RefactoringMethodParameter(p.kind, p.type, p.name, id: p.id);
     }).toList();
   }
 }