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 20df0bca2e168caf3436a6e11e1f4bbb8e0c34d2..e298e7779a15781b804ec983fa96c15c31fe9d4e 100644
--- a/src/image/SkImage_Base.h
+++ b/src/image/SkImage_Base.h
@@ -35,6 +35,13 @@ 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*, SkImageUsageType) const = 0;