Adding the 'filter' context attribute to 2D canvas

Source/core/html/canvas/CanvasRenderingContext2DState.h

Index: Source/core/html/canvas/CanvasRenderingContext2DState.h
diff --git a/Source/core/html/canvas/CanvasRenderingContext2DState.h b/Source/core/html/canvas/CanvasRenderingContext2DState.h
index d9bde289ccbe58535d52117a7e97ada8504ae474..ed5c99ee8c0cf912aae0d3af75d4abf1006832c5 100644
--- a/Source/core/html/canvas/CanvasRenderingContext2DState.h
+++ b/Source/core/html/canvas/CanvasRenderingContext2DState.h
@@ -14,6 +14,8 @@
 namespace blink {
 
 class CanvasStyle;
+class CSSValue;
+class Element;
 
 class CanvasRenderingContext2DState final : public NoBaseWillBeGarbageCollectedFinalized<CanvasRenderingContext2DState>, public CSSFontSelectorClient {
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(CanvasRenderingContext2DState);
@@ -78,6 +80,11 @@ public:
     void setUnparsedFont(const String& font) { m_unparsedFont = font; }
     const String& unparsedFont() const { return m_unparsedFont; }
 
+    void setFilter(PassRefPtrWillBeRawPtr<CSSValue>);
+    void setUnparsedFilter(const String& filterString) { m_unparsedFilter = filterString; }
+    const String& unparsedFilter() const { return m_unparsedFilter; }
+    SkImageFilter* filter(Element*, const Font&) const;
+
     void setStrokeStyle(PassRefPtrWillBeRawPtr<CanvasStyle>);
     CanvasStyle* strokeStyle() const { return m_strokeStyle.get(); }
 
@@ -191,6 +198,10 @@ private:
     String m_unparsedFont;
     Font m_font;
 
+    String m_unparsedFilter;
+    RefPtrWillBeRawPtr<CSSValue> m_filterValue;
+    mutable RefPtr<SkImageFilter> m_resolvedFilter;
+
     // Text state.
     TextAlign m_textAlign;
     TextBaseline m_textBaseline;