Move HashMetricName to base namespace.

components/metrics/metrics_hashes.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/metrics/metrics_hashes.h"
-
-#include "base/logging.h"
-#include "base/md5.h"
-#include "base/sys_byteorder.h"
-
-namespace metrics {
-
-namespace {
-
-// Converts the 8-byte prefix of an MD5 hash into a uint64 value.
-inline uint64 DigestToUInt64(const base::MD5Digest& digest) {
-  uint64 value;
-  DCHECK_GE(arraysize(digest.a), sizeof(value));
-  memcpy(&value, digest.a, sizeof(value));
-  return base::HostToNet64(value);
-}
-
-}  // namespace
-
-uint64 HashMetricName(const std::string& name) {
-  base::MD5Digest digest;
-  base::MD5Sum(name.c_str(), name.size(), &digest);
-  return DigestToUInt64(digest);
-}
-
-}  // namespace metrics