Implement network performance simulation for remoting perf tests.

remoting/test/leaky_bucket.h

+// 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.
+
+#ifndef REMOTING_TEST_LEAKY_BUCKET_H_
+#define REMOTING_TEST_LEAKY_BUCKET_H_
+
+#include "base/basictypes.h"
+#include "base/time/time.h"
+
+namespace remoting {
+
+class LeakyBucket {
+ public:
+  // |depth| is in bytes. |rate| is specified in bytes/second.
+  LeakyBucket(double depth, double rate);
+  ~LeakyBucket();
+
+  // Adds a packet of the given |size| to the bucket and returns packet delay.
+  // Returns TimeDelta::Max() if the packet overflows the bucket, in which case
+  // it should be dropped.
+  base::TimeDelta AddPacket(int size);
+
+ private:
+  void UpdateLevel();
+
+  double depth_;
+  double rate_;
+
+  double level_;
+  base::TimeTicks last_update_;
+
+  DISALLOW_COPY_AND_ASSIGN(LeakyBucket);
+};
+
+}  // namespace remoting
+
+#endif  // REMOTING_TEST_LEAKY_BUCKET_H_