Switch SkImageSource image filter over to new onFilterImage interface

src/core/SkSpecialImage.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file
  */
 
 #ifndef SkSpecialImage_DEFINED
 #define SkSpecialImage_DEFINED
 
@@ skipping 34 matching lines @@
 
     uint32_t uniqueID() const { return fUniqueID; }
     virtual bool isOpaque() const { return false; }
     virtual size_t getSize() const = 0;
 
     /**
      *  Draw this SpecialImage into the canvas.
      */
     void draw(SkCanvas*, SkScalar x, SkScalar y, const SkPaint*) const;
 
-    static SkSpecialImage* NewFromImage(const SkIRect& subset, const SkImage*);
+    static SkSpecialImage* NewFromImage(SkImageFilter::Proxy*,

[Stephen White, 2016/03/07 21:47:26]

Could we instead add a NewFromImageDeprecated() which takes the Proxy, and leave
the existing NewFromImage() in place?

[robertphillips, 2016/03/08 16:45:29]

Well, it now matches the other two entry points. I initially thought I wouldn't
need to carry along the Proxy for SkImage-backed SkSpecialImages but the
non-clipped case in imagesource requires it.

Once all the imagefilters are swapped over they proxy parameter will be removed
from all three entry points.

[Stephen White, 2016/03/08 16:48:42]

Ahh, good point.

+                                        const SkIRect& subset,
+                                        const SkImage*);
     static SkSpecialImage* NewFromRaster(SkImageFilter::Proxy*,
                                          const SkIRect& subset,
                                          const SkBitmap&);
     static SkSpecialImage* NewFromGpu(SkImageFilter::Proxy*,
                                       const SkIRect& subset,
                                       uint32_t uniqueID,
                                       GrTexture*, 
                                       SkAlphaType at = kPremul_SkAlphaType);
 
     /**
@@ skipping 49 matching lines @@
     const uint32_t  fUniqueID;
 
     // TODO: remove this ASAP (see skbug.com/4965)
     SkImageFilter::Proxy* fProxy;
 
     typedef SkRefCnt INHERITED;
 };
 
 #endif