Update from https://crrev.com/304418

net/base/network_activity_monitor.cc

Index: net/base/network_activity_monitor.cc
diff --git a/net/base/network_activity_monitor.cc b/net/base/network_activity_monitor.cc
new file mode 100644
index 0000000000000000000000000000000000000000..78da8c8d4f387be182af3d09b7a0c25b798b3c87
--- /dev/null
+++ b/net/base/network_activity_monitor.cc
@@ -0,0 +1,64 @@
+// Copyright (c) 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 "net/base/network_activity_monitor.h"
+
+namespace net {
+
+namespace {
+
+base::LazyInstance<NetworkActivityMonitor>::Leaky g_network_activity_monitor =
+    LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
+NetworkActivityMonitor::NetworkActivityMonitor()
+    : bytes_received_(0), bytes_sent_(0) {
+}
+
+NetworkActivityMonitor::~NetworkActivityMonitor() {
+}
+
+// static
+NetworkActivityMonitor* NetworkActivityMonitor::GetInstance() {
+  return g_network_activity_monitor.Pointer();
+}
+
+void NetworkActivityMonitor::IncrementBytesReceived(uint64_t bytes_received) {
+  base::TimeTicks now = base::TimeTicks::Now();
+  base::AutoLock lock(lock_);
+  bytes_received_ += bytes_received;
+  last_received_ticks_ = now;
+}
+
+void NetworkActivityMonitor::IncrementBytesSent(uint64_t bytes_sent) {
+  base::TimeTicks now = base::TimeTicks::Now();
+  base::AutoLock lock(lock_);
+  bytes_sent_ += bytes_sent;
+  last_sent_ticks_ = now;
+}
+
+uint64_t NetworkActivityMonitor::GetBytesReceived() const {
+  base::AutoLock lock(lock_);
+  return bytes_received_;
+}
+
+uint64_t NetworkActivityMonitor::GetBytesSent() const {
+  base::AutoLock lock(lock_);
+  return bytes_sent_;
+}
+
+base::TimeDelta NetworkActivityMonitor::GetTimeSinceLastReceived() const {
+  base::TimeTicks now = base::TimeTicks::Now();
+  base::AutoLock lock(lock_);
+  return now - last_received_ticks_;
+}
+
+base::TimeDelta NetworkActivityMonitor::GetTimeSinceLastSent() const {
+  base::TimeTicks now = base::TimeTicks::Now();
+  base::AutoLock lock(lock_);
+  return now - last_sent_ticks_;
+}
+
+}  // namespace net