Removed unused paintInvalidationRect member.

sky/engine/core/rendering/FilterEffectRenderer.h

Index: sky/engine/core/rendering/FilterEffectRenderer.h
diff --git a/sky/engine/core/rendering/FilterEffectRenderer.h b/sky/engine/core/rendering/FilterEffectRenderer.h
index 73c4dd87ef10ffd99185fcf3c3cc0f53573f68f3..c9973619f73c8d3c2ac556f9806cd3dc79dc681f 100644
--- a/sky/engine/core/rendering/FilterEffectRenderer.h
+++ b/sky/engine/core/rendering/FilterEffectRenderer.h
@@ -59,13 +59,10 @@ public:
     bool prepareFilterEffect(RenderLayer*, const LayoutRect& filterBoxRect, const LayoutRect& dirtyRect);
     GraphicsContext* beginFilterEffect(GraphicsContext* oldContext);
     GraphicsContext* applyFilterEffect();
-
-    const LayoutRect& paintInvalidationRect() const { return m_paintInvalidationRect; }
 private:
     GraphicsContext* m_savedGraphicsContext;
     RenderLayer* m_renderLayer;
 
-    LayoutRect m_paintInvalidationRect;
     FloatRect m_filterBoxRect;
     bool m_haveFilterEffect;
 };
@@ -90,7 +87,7 @@ public:
     ImageBuffer* output() const { return lastEffect()->asImageBuffer(); }
 
     bool build(RenderObject* renderer, const FilterOperations&);
-    bool updateBackingStoreRect(const FloatRect& filterRect);
+    void updateBackingStoreRect(const FloatRect& filterRect);
     void allocateBackingStoreIfNeeded();
     void clearIntermediateResults();
     void apply();