Do not use LayoutProgress for a UA shadow element of a PROGRESS element.

third_party/WebKit/Source/core/layout/LayoutProgress.h

 /*
  * Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 12 matching lines @@
 
 #include "core/CoreExport.h"
 #include "core/layout/LayoutBlockFlow.h"
 
 namespace blink {
 
 class HTMLProgressElement;
 
 class CORE_EXPORT LayoutProgress final : public LayoutBlockFlow {
 public:
-    explicit LayoutProgress(HTMLElement*);
+    explicit LayoutProgress(HTMLProgressElement*);
     ~LayoutProgress() override;
 
     double position() const { return m_position; }
     double animationProgress() const;
 
     bool isDeterminate() const;
     void updateFromElement() override;
 
     HTMLProgressElement* progressElement() const;
 
@@ skipping 19 matching lines @@
     Timer<LayoutProgress> m_animationTimer;
 
     friend class LayoutProgressTest;
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutProgress, isProgress());
 
 } // namespace blink
 
 #endif // LayoutProgress_h