Add more Rappor metrics

components/rappor/rappor_utils_unittest.cc

+// Copyright 2014 The Chromium 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 "components/rappor/rappor_utils.h"
+
+#include "components/rappor/rappor_service.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "url/gurl.h"
+
+namespace rappor {
+
+// Make sure we don't crash with a null service.
+TEST(RapporUtilsTest, NullServiceTest) {
+  SampleDomainAndRegistryFromHost(NULL, "", "");

[Peter Kasting, 2014/06/06 02:05:48]

Nit: Use std::string() in place of "" (many places)

[Steven Holte, 2014/06/06 21:00:51]

Done.

+  SampleDomainAndRegistryFromGURL(NULL, "", GURL());
+}
+
+// Make sure recording a sample doesn't cause a crash.
+TEST(RapporUtilsTest, SmokeTest) {
+  RapporService service;
+  SampleDomainAndRegistryFromHost(&service, "", "");
+  SampleDomainAndRegistryFromGURL(&service, "", GURL());
+}
+
+}  // namespace rappor