Get rid of redundant MockSdk.

pkg/analyzer/test/generated/all_the_rest_test.dart

Index: pkg/analyzer/test/generated/all_the_rest_test.dart
diff --git a/pkg/analyzer/test/generated/all_the_rest_test.dart b/pkg/analyzer/test/generated/all_the_rest_test.dart
index 2061e63bb9a9cd47fbfaf35d64d43d10a7db4c59..6dadfa0d86ea42cfe3b4620bd1b3079187e7cfbc 100644
--- a/pkg/analyzer/test/generated/all_the_rest_test.dart
+++ b/pkg/analyzer/test/generated/all_the_rest_test.dart
@@ -3951,32 +3951,6 @@ class FileUriResolverTest {
   }
 }
 
-/**
- * Instances of the class `MockDartSdk` implement a [DartSdk].
- */
-class MockDartSdk implements DartSdk {
-  @override
-  AnalysisContext get context => null;
-
-  @override
-  List<SdkLibrary> get sdkLibraries => null;
-
-  @override
-  String get sdkVersion => null;
-
-  @override
-  List<String> get uris => null;
-
-  @override
-  Source fromFileUri(Uri uri) => null;
-
-  @override
-  SdkLibrary getSdkLibrary(String dartUri) => null;
-
-  @override
-  Source mapDartUri(String dartUri) => null;
-}
-
 @reflectiveTest
 class SDKLibrariesReaderTest extends EngineTestCase {
   void test_readFrom_dart2js() {