Allow SVG images to not taint the canvas with drawImage/drawPattern

Source/core/svg/graphics/SVGImage.h

Index: Source/core/svg/graphics/SVGImage.h
diff --git a/Source/core/svg/graphics/SVGImage.h b/Source/core/svg/graphics/SVGImage.h
index 186f2b74f424d9ea3246e941ec7831c8cd08055d..65a1a0516e50b4f66ec2af97e61dbf1a3c66b39f 100644
--- a/Source/core/svg/graphics/SVGImage.h
+++ b/Source/core/svg/graphics/SVGImage.h
@@ -31,6 +31,7 @@
 
 namespace WebCore {
 
+class Element;
 class FrameView;
 class ImageBuffer;
 class Page;
@@ -45,12 +46,16 @@ public:
         return adoptRef(new SVGImage(observer));
     }
 
+    static bool isInSVGImage(const Element*);
+
     RenderBox* embeddedContentBox() const;
     FrameView* frameView() const;
 
     virtual bool isSVGImage() const OVERRIDE { return true; }
     virtual IntSize size() const OVERRIDE { return m_intrinsicSize; }
 
+    virtual bool hasSingleSecurityOrigin() const OVERRIDE;
+
     virtual bool hasRelativeWidth() const OVERRIDE;
     virtual bool hasRelativeHeight() const OVERRIDE;