[turbofan] Enforce native context specialization.

test/unittests/test-utils.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "test/unittests/test-utils.h"
 
 #include "include/libplatform/libplatform.h"
 #include "src/base/platform/time.h"
 #include "src/debug/debug.h"
 #include "src/flags.h"
@@ skipping 66 matching lines @@
 
 
 namespace internal {
 
 TestWithIsolate::~TestWithIsolate() {}
 
 TestWithIsolateAndZone::~TestWithIsolateAndZone() {}
 
 Factory* TestWithIsolate::factory() const { return isolate()->factory(); }
 
-
 base::RandomNumberGenerator* TestWithIsolate::random_number_generator() const {
   return isolate()->random_number_generator();
 }
 
+TestWithZone::~TestWithZone() {}
 
-TestWithZone::~TestWithZone() {}
+TestWithNativeContext::~TestWithNativeContext() {}
+
+Handle<Context> TestWithNativeContext::native_context() const {
+  return isolate()->native_context();
+}
 
 }  // namespace internal
 }  // namespace v8