Use high precision timestamp for Event.timestamp

third_party/WebKit/Source/core/dom/Document.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2011 Google Inc. All rights reserved.
  *
@@ skipping 893 matching lines @@
     void decrementLoadEventDelayCount();
     void checkLoadEventSoon();
     bool isDelayingLoadEvent();
     void loadPluginsSoon();
 
     PassRefPtrWillBeRawPtr<Touch> createTouch(DOMWindow*, EventTarget*, int identifier, double pageX, double pageY, double screenX, double screenY, double radiusX, double radiusY, float rotationAngle, float force) const;
     PassRefPtrWillBeRawPtr<TouchList> createTouchList(WillBeHeapVector<RefPtrWillBeMember<Touch>>&) const;
 
     const DocumentTiming& timing() const { return m_documentTiming; }
 
+    double monotonicTimeToZeroBasedDocumentTime(double) const;
+
     int requestAnimationFrame(FrameRequestCallback*);
     void cancelAnimationFrame(int id);
     void serviceScriptedAnimations(double monotonicAnimationStartTime);
 
     int requestIdleCallback(IdleRequestCallback*, double timeoutMillis);
     void cancelIdleCallback(int id);
 
     EventTarget* errorEventTarget() final;
     void logExceptionToConsole(const String& errorMessage, int scriptId, const String& sourceURL, int lineNumber, int columnNumber, PassRefPtrWillBeRawPtr<ScriptCallStack>) final;
 
@@ skipping 509 matching lines @@
 DEFINE_TYPE_CASTS(TreeScope, Document, document, true, true);
 
 } // namespace blink
 
 #ifndef NDEBUG
 // Outside the WebCore namespace for ease of invocation from gdb.
 CORE_EXPORT void showLiveDocumentInstances();
 #endif
 
 #endif // Document_h