infer null from context, this avoids bottom being introduced

pkg/analyzer/test/src/summary/resynthesize_ast_test.dart

Index: pkg/analyzer/test/src/summary/resynthesize_ast_test.dart
diff --git a/pkg/analyzer/test/src/summary/resynthesize_ast_test.dart b/pkg/analyzer/test/src/summary/resynthesize_ast_test.dart
index 420d515416113c8bff7e31fc33ef5302404cf74e..a9b6f518e7fcb5e04843a06fa2db01913eea01a9 100644
--- a/pkg/analyzer/test/src/summary/resynthesize_ast_test.dart
+++ b/pkg/analyzer/test/src/summary/resynthesize_ast_test.dart
@@ -144,6 +144,12 @@ class AstInferredTypeTest extends AbstractResynthesizeTest
   }
 
   @override
+  @failingTest
+  void test_bottom() {
+    super.test_bottom();
+  }
+
+  @override
   void test_canInferAlsoFromStaticAndInstanceFieldsFlagOn() {
     variablesWithNotConstInitializers.add('a2');
     super.test_canInferAlsoFromStaticAndInstanceFieldsFlagOn();