shill: vpn: Set the friendly VPN service name.

Also, implement a more concise KeyValueStore string lookup method and add unit
tests.

BUG=chromium-os:27775
TEST=unit tests

Change-Id: If6ab38a9110c09275816bcc6ca992a77425859eb
Reviewed-on: https://gerrit.chromium.org/gerrit/18106
Commit-Ready: Darin Petkov <petkov@chromium.org>
Reviewed-by: Darin Petkov <petkov@chromium.org>
Tested-by: Darin Petkov <petkov@chromium.org>
diff --git a/key_value_store_unittest.cc b/key_value_store_unittest.cc
new file mode 100644
index 0000000..03964da
--- /dev/null
+++ b/key_value_store_unittest.cc
@@ -0,0 +1,27 @@
+// Copyright (c) 2012 The Chromium OS 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 "shill/key_value_store.h"
+
+#include <gtest/gtest.h>
+
+using testing::Test;
+
+namespace shill {
+
+class KeyValueStoreTest : public Test {
+ public:
+  KeyValueStoreTest() {}
+
+ protected:
+  KeyValueStore store_;
+};
+
+TEST_F(KeyValueStoreTest, LookupString) {
+  EXPECT_EQ("bar", store_.LookupString("foo", "bar"));
+  store_.SetString("foo", "zoo");
+  EXPECT_EQ("zoo", store_.LookupString("foo", "bar"));
+}
+
+}  // namespace shill