Adds filter support for offscreen canvas

third_party/WebKit/Source/core/css/resolver/FontBuilder.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.
  * Copyright (C) 2013 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
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 23 matching lines @@
 namespace blink {
 
 class CSSValue;
 class FontSelector;
 class ComputedStyle;
 
 class CORE_EXPORT FontBuilder {
     STACK_ALLOCATED();
     WTF_MAKE_NONCOPYABLE(FontBuilder);
 public:
+    FontBuilder();

[esprehn, 2016/09/12 20:53:12]

A FontBuilder without a document crashes all over the place

     FontBuilder(const Document&);
 
     void setInitial(float effectiveZoom);
 
     void didChangeEffectiveZoom();
     void didChangeTextOrientation();
     void didChangeWritingMode();
 
     FontFamily standardFontFamily() const;
     AtomicString standardFontFamilyName() const;
@@ skipping 78 matching lines @@
 
     void set(PropertySetFlag flag) { m_flags |= (1 << unsigned(flag)); }
     bool isSet(PropertySetFlag flag) const { return m_flags & (1 << unsigned(flag)); }
 
     unsigned m_flags;
 };
 
 } // namespace blink
 
 #endif