Adds filter support for offscreen canvas

third_party/WebKit/Source/core/css/resolver/StyleResolverState.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple 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
  * 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,
@@ skipping 29 matching lines @@
 #include <memory>
 
 namespace blink {
 
 class FontDescription;
 
 class CORE_EXPORT StyleResolverState {
     STACK_ALLOCATED();
     WTF_MAKE_NONCOPYABLE(StyleResolverState);
 public:
+    StyleResolverState(const ComputedStyle* parentStyle);
     StyleResolverState(Document&, const ElementResolveContext&, const ComputedStyle* parentStyle);
     StyleResolverState(Document&, Element*, const ComputedStyle* parentStyle = 0);
     ~StyleResolverState();
 
     // In FontFaceSet and CanvasRenderingContext2D, we don't have an element to grab the document from.
     // This is why we have to store the document separately.
+    bool hasDocument() const { return m_document; }
     Document& document() const { return *m_document; }
     // These are all just pass-through methods to ElementResolveContext.
     Element* element() const { return m_elementContext.element(); }
     const ContainerNode* parentNode() const { return m_elementContext.parentNode(); }
     const ComputedStyle* rootElementStyle() const { return m_elementContext.rootElementStyle(); }
     EInsideLink elementLinkState() const { return m_elementContext.elementLinkState(); }
     bool distributedToInsertionPoint() const { return m_elementContext.distributedToInsertionPoint(); }
 
     const ElementResolveContext& elementContext() const { return m_elementContext; }
 
     void setStyle(PassRefPtr<ComputedStyle> style)
     {
         // FIXME: Improve RAII of StyleResolverState to remove this function.
         m_style = style;
-        m_cssToLengthConversionData = CSSToLengthConversionData(m_style.get(), rootElementStyle(), document().layoutViewItem(), m_style->effectiveZoom());
+        if (m_document) {
+            m_cssToLengthConversionData = CSSToLengthConversionData(m_style.get(), rootElementStyle(), document().layoutViewItem(), m_style->effectiveZoom());
+        } else {
+            m_cssToLengthConversionData = CSSToLengthConversionData(m_style.get(), m_style->effectiveZoom());
+        }
     }
     const ComputedStyle* style() const { return m_style.get(); }
     ComputedStyle* style() { return m_style.get(); }
     PassRefPtr<ComputedStyle> takeStyle() { return m_style.release(); }
 
     ComputedStyle& mutableStyleRef() const { return *m_style; }
     const ComputedStyle& styleRef() const { return mutableStyleRef(); }
 
     const CSSToLengthConversionData& cssToLengthConversionData() const { return m_cssToLengthConversionData; }
     CSSToLengthConversionData fontSizeConversionData() const;
@@ skipping 109 matching lines @@
 
     HeapHashMap<String, Member<StylePropertySet>> m_customPropertySetsForApplyAtRule;
 
     HeapHashMap<Member<const CSSPendingSubstitutionValue>, Member<HeapHashMap<CSSPropertyID, Member<const CSSValue>>>> m_parsedPropertiesForPendingSubstitution;
 
 };
 
 } // namespace blink
 
 #endif // StyleResolverState_h