Add a simple microbenchmark framework, packaging, and sample tests.

src/platform/microbenchmark/main.cc

+// Copyright (c) 2009 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.
+// Some portions Copyright (c) 2009 The Chromium Authors.
+
+#include "microbenchmark/microbenchmark.h"
+
+#include <stdlib.h>
+
+int main(int argc, char **argv) {
+  CommandLine::Init(argc, argv);
+  logging::InitLogging(NULL,
+                       logging::LOG_ONLY_TO_SYSTEM_DEBUG_LOG,
+                       logging::DONT_LOCK_LOG_FILE,
+                       logging::APPEND_TO_OLD_LOG_FILE);
+  ::testing::InitGoogleTest(&argc, argv);
+  CommandLine *cl = CommandLine::ForCurrentProcess();
+  if (cl->GetSwitchValueASCII(chromeos::Microbenchmark::kRunsSwitch).empty()) {
+    LOG(INFO) << "Defaulting to the number of runs specified per test";
+    LOG(INFO) << "To override, use --"
+              << chromeos::Microbenchmark::kRunsSwitch
+              << "=NUM";
+  }
+  return RUN_ALL_TESTS();
+}