Switch SkAutoMalloc to SkAutoTMalloc to avoid cast

src/codec/SkJpegCodec.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkJpegCodec_DEFINED
 #define SkJpegCodec_DEFINED
 
 #include "SkCodec.h"
 #include "SkImageInfo.h"
 #include "SkJpegDecoderMgr.h"
 #include "SkJpegUtility_codec.h"
 #include "SkStream.h"
+#include "SkTemplates.h"
 
 extern "C" {
     #include "jpeglib.h"
 }
 
 /*
  *
  * This class implements the decoding for jpeg images
  *
  */
@@ skipping 78 matching lines @@
             SkPMColor ctable[], int* ctableCount) override;
     int onGetScanlines(void* dst, int count, size_t rowBytes) override;
     bool onSkipScanlines(int count) override;
 
     SkAutoTDelete<JpegDecoderMgr> fDecoderMgr;
     // We will save the state of the decompress struct after reading the header.
     // This allows us to safely call onGetScaledDimensions() at any time.
     const int                     fReadyState;
 
     // scanline decoding
-    SkAutoMalloc               fStorage;    // Only used if sampling is needed
+    SkAutoTMalloc<uint8_t>     fStorage;    // Only used if sampling is needed
     uint8_t*                   fSrcRow;     // Only used if sampling is needed
     SkAutoTDelete<SkSwizzler>  fSwizzler;
     
     typedef SkCodec INHERITED;
 };
 
 #endif