Generated front_end/testcases/inference test files from Analyzer tests.

pkg/front_end/testcases/inference/null_coalescing_operator_2.dart

Index: pkg/front_end/testcases/inference/null_coalescing_operator_2.dart
diff --git a/pkg/front_end/testcases/inference/null_coalescing_operator_2.dart b/pkg/front_end/testcases/inference/null_coalescing_operator_2.dart
new file mode 100644
index 0000000000000000000000000000000000000000..3900d5a0ff3b9616f02ea30032233007cc98dad9
--- /dev/null
+++ b/pkg/front_end/testcases/inference/null_coalescing_operator_2.dart
@@ -0,0 +1,11 @@
+// Copyright (c) 2017, 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.
+
+/*@testedFeatures=inference*/
+library test;
+
+main() {
+  List<int> x;
+  List<num> y = /*@promotedType=none*/ x ?? /*@typeArgs=num*/ [];
+}