Remove List.map from analyzer's mock SDK

pkg/analyzer/test/src/context/mock_sdk.dart

Index: pkg/analyzer/test/src/context/mock_sdk.dart
diff --git a/pkg/analyzer/test/src/context/mock_sdk.dart b/pkg/analyzer/test/src/context/mock_sdk.dart
index 65ba4417d15553a919a5802adb206c0555c804cf..c7fa7c7767580ca2f33582f7463a5ddf3b9e3cd0 100644
--- a/pkg/analyzer/test/src/context/mock_sdk.dart
+++ b/pkg/analyzer/test/src/context/mock_sdk.dart
@@ -284,8 +284,6 @@ class List<E> implements Iterable<E> {
   E get first => null;
   E get last => null;
 
-  Iterable/*<R>*/ map/*<R>*/(/*=R*/ f(E e)) => null;
-
   /*=R*/ fold/*<R>*/(/*=R*/ initialValue,
       /*=R*/ combine(/*=R*/ previousValue, E element)) => null;