add applyFilter() to SkImage

src/image/SkImage_Base.h

Index: src/image/SkImage_Base.h
diff --git a/src/image/SkImage_Base.h b/src/image/SkImage_Base.h
index 7819e9c19d11cfb6521c828f055895de49b93396..3fe3444aef976245979dd886349fe561dc2c077e 100644
--- a/src/image/SkImage_Base.h
+++ b/src/image/SkImage_Base.h
@@ -37,6 +37,13 @@ public:
     // but only inspect them (or encode them).
     virtual bool getROPixels(SkBitmap*) const = 0;
 
+    virtual SkImage* onApplyFilter(SkImageFilter*, SkIPoint* offset,
+                                   bool forceResultToOriginalSize) const;
+
+    virtual SkSurface* onNewSurface(const SkImageInfo& info) const {
+        return SkSurface::NewRaster(info);
+    }
+
     // Caller must call unref when they are done.
     virtual GrTexture* asTextureRef(GrContext*, const GrTextureParams&) const = 0;