Make SkImageFilter crop rects relative to the primitive origin, instead of relative to their parent

src/core/SkImageFilter.cpp

 /*
  * Copyright 2012 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkImageFilter.h"
 
 #include "SkBitmap.h"
@@ skipping 75 matching lines @@
         if (input != NULL) {
             buffer.writeFlattenable(input);
         }
     }
     buffer.writeRect(fCropRect.rect());
     buffer.writeUInt(fCropRect.flags());
 }
 
 bool SkImageFilter::filterImage(Proxy* proxy, const SkBitmap& src,
                                 const SkMatrix& ctm,
-                                SkBitmap* result, SkIPoint* loc) {
+                                SkBitmap* result, SkIPoint* offset) {
     SkASSERT(result);
-    SkASSERT(loc);
+    SkASSERT(offset);
     /*
      *  Give the proxy first shot at the filter. If it returns false, ask
      *  the filter to do it.
      */
-    return (proxy && proxy->filterImage(this, src, ctm, result, loc)) ||
-           this->onFilterImage(proxy, src, ctm, result, loc);
+    return (proxy && proxy->filterImage(this, src, ctm, result, offset)) ||
+           this->onFilterImage(proxy, src, ctm, result, offset);
 }
 
 bool SkImageFilter::filterBounds(const SkIRect& src, const SkMatrix& ctm,
                                  SkIRect* dst) {
     SkASSERT(&src);
     SkASSERT(dst);
     return this->onFilterBounds(src, ctm, dst);
 }
 
 bool SkImageFilter::onFilterImage(Proxy*, const SkBitmap&, const SkMatrix&,
@@ skipping 74 matching lines @@
     return true;
 }
 
 bool SkImageFilter::asNewEffect(GrEffectRef**, GrTexture*, const SkMatrix&, const SkIRect&) const {
     return false;
 }
 
 bool SkImageFilter::asColorFilter(SkColorFilter**) const {
     return false;
 }