Add more Rappor metrics

chrome/browser/rappor/sampling_unittest.cc

Index: chrome/browser/rappor/sampling_unittest.cc
diff --git a/chrome/browser/rappor/sampling_unittest.cc b/chrome/browser/rappor/sampling_unittest.cc
new file mode 100644
index 0000000000000000000000000000000000000000..1dc9cb95ccdc3e167a31f02432762c32b8ca94a7
--- /dev/null
+++ b/chrome/browser/rappor/sampling_unittest.cc
@@ -0,0 +1,18 @@
+// 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 "chrome/browser/rappor/sampling.h"
+
+#include "testing/gtest/include/gtest/gtest.h"
+#include "url/gurl.h"
+
+namespace rappor {
+
+// Make sure recording a sample doesn't cause a crash.

[Peter Kasting, 2014/06/09 00:51:14]

Nit: Did you mean "recording a sample from an empty host/GURL"?  (As it stands
the reader wonders why just "recording a sample" might risk crashing.  Or is the
Rappor service NULL in tests?  If so maybe refer to recording a sample with a
NULL service?)

[Steven Holte, 2014/06/09 17:54:29]

Done.

+TEST(RapporSamplingTest, SmokeTest) {
+  SampleDomainAndRegistryFromHost(std::string(), std::string());
+  SampleDomainAndRegistryFromGURL(std::string(), GURL());
+}
+
+}  // namespace rappor