blink: Add backdrop-filter support

Source/core/layout/LayoutObject.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  *           (C) 2000 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
@@ skipping 550 matching lines @@
     bool hasClip() const { return isOutOfFlowPositioned() && !style()->hasAutoClip(); }
     bool hasOverflowClip() const { return m_bitfields.hasOverflowClip(); }
     bool hasClipOrOverflowClip() const { return hasClip() || hasOverflowClip(); }
 
     bool hasTransformRelatedProperty() const { return m_bitfields.hasTransformRelatedProperty(); }
     bool hasMask() const { return style() && style()->hasMask(); }
     bool hasClipPath() const { return style() && style()->clipPath(); }
     bool hasHiddenBackface() const { return style() && style()->backfaceVisibility() == BackfaceVisibilityHidden; }
 
     bool hasFilter() const { return style() && style()->hasFilter(); }
+    bool hasBackdropFilter() const { return style() && style()->hasBackdropFilter(); }
 
     bool hasShapeOutside() const { return style() && style()->shapeOutside(); }
 
     inline bool preservesNewline() const;
 
     // The pseudo element style can be cached or uncached.  Use the cached method if the pseudo element doesn't respect
     // any pseudo classes (and therefore has no concept of changing state).
     ComputedStyle* getCachedPseudoStyle(PseudoId, const ComputedStyle* parentStyle = nullptr) const;
     PassRefPtr<ComputedStyle> getUncachedPseudoStyle(const PseudoStyleRequest&, const ComputedStyle* parentStyle = nullptr, const ComputedStyle* ownStyle = nullptr) const;
 
@@ skipping 1088 matching lines @@
 void showTree(const blink::LayoutObject*);
 void showLineTree(const blink::LayoutObject*);
 void showLayoutTree(const blink::LayoutObject* object1);
 // We don't make object2 an optional parameter so that showLayoutTree
 // can be called from gdb easily.
 void showLayoutTree(const blink::LayoutObject* object1, const blink::LayoutObject* object2);
 
 #endif
 
 #endif // LayoutObject_h