Make SkPngCodec decode progressively.

fuzz/fuzz.cpp

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "Fuzz.h"
 #include "SkCanvas.h"
 #include "SkCodec.h"
@@ skipping 169 matching lines @@
                     SkDebugf("[terminated] Could not start scanline decoder\n");
                     return 7;
                 }
 
             void* dst = bitmap.getAddr(0, 0);
             size_t rowBytes = bitmap.rowBytes();
             uint32_t height = decodeInfo.height();
             switch (codec->getScanlineOrder()) {
                 case SkCodec::kTopDown_SkScanlineOrder:
                 case SkCodec::kBottomUp_SkScanlineOrder:
-                case SkCodec::kNone_SkScanlineOrder:
                     // We do not need to check the return value.  On an incomplete
                     // image, memory will be filled with a default value.
                     codec->getScanlines(dst, height, rowBytes);
                     break;
                 case SkCodec::kOutOfOrder_SkScanlineOrder: {
                     for (int y = 0; y < decodeInfo.height(); y++) {
                         int dstY = codec->outputScanline(y);
                         void* dstPtr = bitmap.getAddr(0, dstY);
                         // We complete the loop, even if this call begins to fail
                         // due to an incomplete image.  This ensures any uninitialized
@@ skipping 216 matching lines @@
     if (min > max) {
         SkDebugf("Check mins and maxes (%f, %f)\n", min, max);
         this->signalBoring();
     }
     float f = std::abs(this->nextF());
     if (!std::isnormal(f) && f != 0.0) {
         this->signalBoring();
     }
     return min + fmod(f, (max - min + 1));
 }