Reenable warnings in src/codec

src/codec/SkBmpMaskCodec.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 "SkBmpMaskCodec.h"
 #include "SkCodecPriv.h"
 #include "SkColorPriv.h"
@@ skipping 32 matching lines @@
     if (!conversion_possible(dstInfo, this->getInfo())) {
         SkCodecPrintf("Error: cannot convert input type to output type.\n");
         return kInvalidConversion;
     }
 
     Result result = this->prepareToDecode(dstInfo, opts, inputColorPtr, inputColorCount);
     if (kSuccess != result) {
         return result;
     }
 
-    uint32_t rows = this->decodeRows(dstInfo, dst, dstRowBytes, opts);
+    int rows = this->decodeRows(dstInfo, dst, dstRowBytes, opts);
     if (rows != dstInfo.height()) {
         *rowsDecoded = rows;
         return kIncompleteInput;
     }
     return kSuccess;
 }
 
 bool SkBmpMaskCodec::initializeSwizzler(const SkImageInfo& dstInfo, const Options& options) {
     // Create the swizzler
     fMaskSwizzler.reset(SkMaskSwizzler::CreateMaskSwizzler(dstInfo, this->getInfo(), fMasks,
@@ skipping 35 matching lines @@
 
         // Decode the row in destination format
         uint32_t row = this->getDstRow(y, height);
         void* dstRow = SkTAddOffset<void>(dst, row * dstRowBytes);
         fMaskSwizzler->swizzle(dstRow, srcRow);
     }
 
     // Finished decoding the entire image
     return height;
 }