Move MockSdk into tests.

test/rule_test.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 linter.test.rule;
 
 import 'dart:io';
 
+import 'mock_sdk.dart';
 import 'package:analyzer/src/generated/engine.dart';
 import 'package:analyzer/src/generated/error.dart';
 import 'package:analyzer/src/generated/source.dart';
 import 'package:linter/src/ast.dart';
 import 'package:linter/src/formatter.dart';
 import 'package:linter/src/io.dart';
 import 'package:linter/src/linter.dart';
 import 'package:linter/src/rules.dart';
 import 'package:linter/src/rules/camel_case_types.dart';
 import 'package:linter/src/rules/implementation_imports.dart';
@@ skipping 383 matching lines @@
       ++lineNumber;
     }
 
     LintRule rule = ruleRegistry[ruleName];
     if (rule == null) {
       print('WARNING: Test skipped -- rule `$ruleName` is not registered.');
       return;
     }
 
     LinterOptions options = new LinterOptions([rule])
-      ..useMockSdk = true
+      ..mockSdk = new MockSdk()
       ..packageRootPath = '.';
 
     DartLinter driver = new DartLinter(options);
 
     Iterable<AnalysisErrorInfo> lints = driver.lintFiles([file]);
 
     List<Annotation> actual = [];
     lints.forEach((AnalysisErrorInfo info) {
       info.errors.forEach((AnalysisError error) {
         if (error.errorCode.type == ErrorType.LINT) {
@@ skipping 84 matching lines @@
 
 class NoFilter implements LintFilter {
   @override
   bool filter(AnalysisError lint) => false;
 }
 
 class ResultReporter extends DetailedReporter {
   ResultReporter(Iterable<AnalysisErrorInfo> errors)
       : super(errors, new NoFilter(), stdout);
 }