Fix recursive computation of filter bounds for drop shadow,

src/effects/SkDropShadowImageFilter.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkDropShadowImageFilter.h"
 
 #include "SkBitmap.h"
@@ skipping 103 matching lines @@
     SkRect shadowBounds = *dst;
     shadowBounds.offset(fDx, fDy);
     shadowBounds.outset(SkScalarMul(fSigmaX, SkIntToScalar(3)),
                         SkScalarMul(fSigmaY, SkIntToScalar(3)));
     dst->join(shadowBounds);
 }
 
 bool SkDropShadowImageFilter::onFilterBounds(const SkIRect& src, const SkMatrix& ctm,
                                              SkIRect* dst) const {
     SkIRect bounds = src;
-    if (getInput(0) && !getInput(0)->filterBounds(src, ctm, &bounds)) {
-        return false;
-    }
     SkVector offsetVec = SkVector::Make(fDx, fDy);
     ctm.mapVectors(&offsetVec, 1);
     bounds.offset(-SkScalarCeilToInt(offsetVec.x()),
                   -SkScalarCeilToInt(offsetVec.y()));
     SkVector sigma = SkVector::Make(fSigmaX, fSigmaY);
     ctm.mapVectors(&sigma, 1);
     bounds.outset(SkScalarCeilToInt(SkScalarMul(sigma.x(), SkIntToScalar(3))),
                   SkScalarCeilToInt(SkScalarMul(sigma.y(), SkIntToScalar(3))));
     bounds.join(src);
+    if (getInput(0) && !getInput(0)->filterBounds(bounds, ctm, &bounds)) {
+        return false;
+    }
     *dst = bounds;
     return true;
 }