cashew: add local byte counters

src/byte_counter.cc

+// Copyright (c) 2010 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 "src/byte_counter.h"
+
+#include <glog/logging.h>
+
+#include "src/procfs_byte_counter.h"
+
+namespace cashew {
+
+// static
+ByteCounter* ByteCounter::NewByteCounter(const std::string& interface) {
+  DCHECK(!interface.empty());
+  return new(std::nothrow) ProcfsByteCounter(interface);
+}
+
+}  // namespace cashew