Create NetworkQuietDetector.

third_party/WebKit/Source/core/loader/NetworkQuietDetector.h

Index: third_party/WebKit/Source/core/loader/NetworkQuietDetector.h
diff --git a/third_party/WebKit/Source/core/loader/NetworkQuietDetector.h b/third_party/WebKit/Source/core/loader/NetworkQuietDetector.h
new file mode 100644
index 0000000000000000000000000000000000000000..403cd2bb5d47c56cbc85faef897d9d6eee2e8bab
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+++ b/third_party/WebKit/Source/core/loader/NetworkQuietDetector.h
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+// Copyright 2017 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 NetworkQuietDetector_h
+#define NetworkQuietDetector_h
+
+#include "core/CoreExport.h"
+#include "platform/Timer.h"
+#include "platform/heap/Handle.h"
+#include "platform/wtf/HashSet.h"
+#include "platform/wtf/Noncopyable.h"
+
+namespace blink {
+
+class Document;
+
+// NetworkQuietDetector observes network request count everytime a load is
+// finshed after DOMLoadedEventEnd is fired, and signals a network idleness
+// signal to GRC when there are no more than 2 network connection active during
+// 1 second.
+class CORE_EXPORT NetworkQuietDetector
+    : public GarbageCollectedFinalized<NetworkQuietDetector> {
+  WTF_MAKE_NONCOPYABLE(NetworkQuietDetector);
+
+ public:
+  NetworkQuietDetector(Document*);
+  virtual ~NetworkQuietDetector() {}
+
+  void CheckNetworkStable();
+
+  DECLARE_TRACE();
+
+ private:
+  friend class NetworkQuietDetectorTest;
+
+  // The page is n-quiet if there are no more than n active network requests for
+  // this duration of time.
+  static constexpr double kNetwork2QuietWindowSeconds = 1.0;
+
+  int ActiveConnections();
+  void SetNetworkQuietTimers(int active_connections);
+  void Network2QuietTimerFired(TimerBase*);
+
+  bool network2_quiet_reached_ = false;
+  Member<Document> document_;
+  TaskRunnerTimer<NetworkQuietDetector> network2_quiet_timer_;
+};
+
+}  // namespace blink
+
+#endif