Allow single-pass filters (which use asNewEffect()) to participate in the image filter DAG. This w…

include/core/SkImageFilter.h

Index: include/core/SkImageFilter.h
diff --git a/include/core/SkImageFilter.h b/include/core/SkImageFilter.h
index 6cc53c0de0ad16711cd3f8448f6584c86d1b0fda..ff034534f6d1504ca992164ab27f4ac8e7380397 100644
--- a/include/core/SkImageFilter.h
+++ b/include/core/SkImageFilter.h
@@ -93,7 +93,7 @@ public:
      *  The effect can assume its vertexCoords space maps 1-to-1 with texels
      *  in the texture.
      */
-    virtual bool asNewEffect(GrEffectRef** effect, GrTexture*) const;
+    virtual GrEffectRef* asNewEffect(GrTexture*) const;
 
     /**
      *  Returns true if the filter can be processed on the GPU.  This is most
@@ -104,11 +104,14 @@ public:
     virtual bool canFilterImageGPU() const;
 
     /**
-     *  Process this image filter on the GPU.  src is the source image for
-     *  processing, as a texture-backed bitmap.  result is the destination
-     *  bitmap, which should contain a texture-backed pixelref on success.
-     *  The default implementation returns returns false and ignores the
-     *  result parameter.
+     *  Process this image filter on the GPU.  This is most often used for 
+     *  multi-pass efefects, where intermediate results must be rendered to
+     *  textures.  For single-pass effects, use asNewEffect().  src is the
+     *  source image for processing, as a texture-backed bitmap.  result is
+     *  the destination bitmap, which should contain a texture-backed pixelref
+     *  on success.  The default implementation does single-pass processing
+     *  using asNewEffect().  If asNewEffect() returns NULL, the default 
+     *  implementation returns false.
      */
     virtual bool filterImageGPU(Proxy*, const SkBitmap& src, SkBitmap* result);