Initial error handling code

include/core/SkImageFilter.h

Index: include/core/SkImageFilter.h
diff --git a/include/core/SkImageFilter.h b/include/core/SkImageFilter.h
index 3dc145ca1979a40e966c352312c576193176fb26..d74a47638e3f7d93d8d88e1e4bc81e4df1597d84 100644
--- a/include/core/SkImageFilter.h
+++ b/include/core/SkImageFilter.h
@@ -28,6 +28,8 @@ class GrTexture;
  *  is what will finally be drawn to the device (using the original xfermode).
  */
 class SK_API SkImageFilter : public SkFlattenable {
+    typedef SkFlattenable INHERITED;
+
 public:
     SK_DECLARE_INST_COUNT(SkImageFilter)
 
@@ -140,6 +142,8 @@ public:
      */
     const SkIRect& cropRect() const { return fCropRect; }
 
+    SK_DEFINE_FLATTENABLE_TYPE(SkImageFilter)
+
 protected:
     SkImageFilter(int inputCount, SkImageFilter** inputs, const SkIRect* cropRect = NULL);
 
@@ -167,7 +171,6 @@ protected:
     bool applyCropRect(SkIRect* rect, const SkMatrix& matrix) const;
 
 private:
-    typedef SkFlattenable INHERITED;
     int fInputCount;
     SkImageFilter** fInputs;
     SkIRect fCropRect;