add hard-coded limit for tmp allocations when HQ image scaling

src/core/SkConvolver.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SK_CONVOLVER_H
 #define SK_CONVOLVER_H
 
 #include "SkSize.h"
 #include "SkTypes.h"
 #include "SkTArray.h"
@@ skipping 175 matching lines @@
 // size will be xfilter.numValues() * yfilter.numValues() pixels. It will be
 // in rows of exactly xfilter.numValues() * 4 bytes.
 //
 // |sourceHasAlpha| is a hint that allows us to avoid doing computations on
 // the alpha channel if the image is opaque. If you don't know, set this to
 // true and it will work properly, but setting this to false will be a few
 // percent faster if you know the image is opaque.
 //
 // The layout in memory is assumed to be 4-bytes per pixel in B-G-R-A order
 // (this is ARGB when loaded into 32-bit words on a little-endian machine).
-SK_API void BGRAConvolve2D(const unsigned char* sourceData,
+/**
+ *  Returns false if it was unable to perform the convolution/rescale. in which case the output
+ *  buffer is assumed to be undefined.
+ */
+SK_API bool BGRAConvolve2D(const unsigned char* sourceData,
     int sourceByteRowStride,
     bool sourceHasAlpha,
     const SkConvolutionFilter1D& xfilter,
     const SkConvolutionFilter1D& yfilter,
     int outputByteRowStride,
     unsigned char* output,
     const SkConvolutionProcs&,
     bool useSimdIfPossible);
 
 #endif  // SK_CONVOLVER_H