Fix MSAN - mark temporary memory as kNo_ZeroInitialized

src/codec/SkPngCodec.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkCodecPriv.h"
 #include "SkColorPriv.h"
@@ skipping 800 matching lines @@
     if (setjmp(png_jmpbuf(fPng_ptr))) {
         SkCodecPrintf("Failed on png_read_update_info.\n");
         return false;
     }
     png_read_update_info(fPng_ptr, fInfo_ptr);
 
     // It's important to reset fColorXform to nullptr.  We don't do this on rewinding
     // because the interlaced scanline decoder may need to rewind.
     fColorXform = nullptr;
     SkImageInfo swizzlerInfo = dstInfo;
+    Options swizzlerOptions = options;
     bool needsColorXform = needs_color_xform(dstInfo, this->getInfo());
     if (needsColorXform) {
         switch (dstInfo.colorType()) {
             case kRGBA_8888_SkColorType:
             case kBGRA_8888_SkColorType:
             case kRGBA_F16_SkColorType:
                 swizzlerInfo = swizzlerInfo.makeColorType(kRGBA_8888_SkColorType);
                 if (kPremul_SkAlphaType == dstInfo.alphaType()) {
                     swizzlerInfo = swizzlerInfo.makeAlphaType(kUnpremul_SkAlphaType);
                 }
                 break;
             case kIndex_8_SkColorType:
                 break;
             default:
                 return false;
         }
 
         fColorXform = SkColorSpaceXform::New(sk_ref_sp(this->getInfo().colorSpace()),
                                              sk_ref_sp(dstInfo.colorSpace()));
 
         if (!fColorXform && kRGBA_F16_SkColorType == dstInfo.colorType()) {
             return false;
         }
+
+        // When there is a color xform, we swizzle into temporary memory, which is not
+        // zero initialized.
+        // FIXME (msarett):
+        // Is this a problem?
+        swizzlerOptions.fZeroInitialized = kNo_ZeroInitialized;
     }
 
     if (SkEncodedInfo::kPalette_Color == this->getEncodedInfo().color()) {
         if (!this->createColorTable(dstInfo, ctableCount)) {
             return false;
         }
     }
 
     // Copy the color table to the client if they request kIndex8 mode
     copy_color_table(swizzlerInfo, fColorTable, ctable, ctableCount);
 
     // Create the swizzler.  SkPngCodec retains ownership of the color table.
     const SkPMColor* colors = get_color_ptr(fColorTable.get());
     fSwizzler.reset(SkSwizzler::CreateSwizzler(this->getEncodedInfo(), colors, swizzlerInfo,
-                                               options));
+                                               swizzlerOptions));
     SkASSERT(fSwizzler);
     return true;
 }
 
 bool SkPngCodec::onRewind() {
     // This sets fPng_ptr and fInfo_ptr to nullptr. If read_header
     // succeeds, they will be repopulated, and if it fails, they will
     // remain nullptr. Any future accesses to fPng_ptr and fInfo_ptr will
     // come through this function which will rewind and again attempt
     // to reinitialize them.
@@ skipping 48 matching lines @@
     SkCodec* outCodec;
     if (read_header(stream, chunkReader, &outCodec, nullptr, nullptr)) {
         // Codec has taken ownership of the stream.
         SkASSERT(outCodec);
         streamDeleter.release();
         return outCodec;
     }
 
     return nullptr;
 }