ImageBuffer-less SVG masking and clipping.

Source/core/platform/graphics/GraphicsContext.h

Index: Source/core/platform/graphics/GraphicsContext.h
diff --git a/Source/core/platform/graphics/GraphicsContext.h b/Source/core/platform/graphics/GraphicsContext.h
index b91c7e6b60245eea6e9bd9aba3b6a6773bac7b68..cc1978441351b563bbe9ed4bc6dbf876741fab20 100644
--- a/Source/core/platform/graphics/GraphicsContext.h
+++ b/Source/core/platform/graphics/GraphicsContext.h
@@ -195,6 +195,8 @@ public:
 
     AnnotationModeFlags annotationMode() const { return m_annotationMode; }
     void setAnnotationMode(const AnnotationModeFlags mode) { m_annotationMode = mode; }
+
+    void setColorSpaceConversion(ColorSpace srcColorSpace, ColorSpace dstColorSpace);
     // ---------- End state management methods -----------------
 
     // Get the contents of the image buffer
@@ -278,7 +280,6 @@ public:
     void clipOutRoundedRect(const RoundedRect&);
     void clipPath(const Path&, WindRule = RULE_EVENODD);
     void clipConvexPolygon(size_t numPoints, const FloatPoint*, bool antialias = true);
-    void clipToImageBuffer(const ImageBuffer*, const FloatRect&);
     bool clipRect(const SkRect&, AntiAliasingMode = NotAntiAliased, SkRegion::Op = SkRegion::kIntersect_Op);
 
     void drawText(const Font&, const TextRunPaintInfo&, const FloatPoint&);
@@ -293,8 +294,9 @@ public:
     };
     void drawLineForDocumentMarker(const FloatPoint&, float width, DocumentMarkerLineStyle);
 
-    void beginTransparencyLayer(float opacity);
-    void endTransparencyLayer();
+    void beginTransparencyLayer(float opacity, const FloatRect* = 0);
+    void beginMaskedLayer(const FloatRect&, MaskType = AlphaMaskType);
+    void endLayer();
 
     bool hasShadow() const;
     void setShadow(const FloatSize& offset, float blur, const Color&,
@@ -408,11 +410,6 @@ private:
 
     bool concat(const SkMatrix&);
 
-    // Used when restoring and the state has an image clip. Only shows the pixels in
-    // m_canvas that are also in imageBuffer.
-    // The clipping rectangle is given in absolute coordinates.
-    void applyClipFromImage(const SkRect&, const SkBitmap&);
-
     // common code between setupPaintFor[Filling,Stroking]
     void setupShader(SkPaint*, Gradient*, Pattern*, SkColor) const;
 
@@ -450,7 +447,7 @@ private:
 
 #if !ASSERT_DISABLED
     unsigned m_annotationCount;
-    unsigned m_transparencyCount;
+    unsigned m_layerCount;
 #endif
     // Tracks the region painted opaque via the GraphicsContext.
     OpaqueRegionSkia m_opaqueRegion;