Issue 27358. Reset AnalysisContext 'sourceFactory' and 'typeSystem' on analysis options change.

pkg/analysis_server/test/mock_sdk.dart

Index: pkg/analysis_server/test/mock_sdk.dart
diff --git a/pkg/analysis_server/test/mock_sdk.dart b/pkg/analysis_server/test/mock_sdk.dart
index 0d39a192e724dabd6c339bf262c4e3a969fc56e0..94d1208e87bd6e29002678275ada5cc187c252bb 100644
--- a/pkg/analysis_server/test/mock_sdk.dart
+++ b/pkg/analysis_server/test/mock_sdk.dart
@@ -126,10 +126,12 @@ class Iterator<E> {
 abstract class Iterable<E> {
   Iterator<E> get iterator;
   bool get isEmpty;
+  Iterable/*<R>*/ map/*<R>*/(/*=R*/ f(E e));
 }
 
 abstract class List<E> implements Iterable<E> {
   void add(E value);
+  void addAll(Iterable<E> iterable) {}
   E operator [](int index);
   void operator []=(int index, E value);
   Iterator<E> get iterator => null;