Switch SkAutoMalloc to SkAutoTMalloc to avoid cast

src/images/SkImageDecoder_libgif.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkColor.h"
 #include "SkColorPriv.h"
 #include "SkColorTable.h"
@@ skipping 360 matching lines @@
                 }
             }
 
             // abort if either inner dimension is <= 0
             if (innerWidth <= 0 || innerHeight <= 0) {
                 return error_return(*bm, "non-pos inner width/height");
             }
 
             SkAutoLockPixels alp(*bm);
 
-            SkAutoMalloc storage(innerWidth);
-            uint8_t* scanline = (uint8_t*) storage.get();
+            SkAutoTMalloc<uint8_t> storage(innerWidth);
+            uint8_t* scanline = storage.get();
 
             // GIF has an option to store the scanlines of an image, plus a larger background,
             // filled by a fill color. In this case, we will use a subset of the larger bitmap
             // for sampling.
             SkBitmap subset;
             SkBitmap* workingBitmap;
             // are we only a subset of the total bounds?
             if ((imageTop | imageLeft) > 0 ||
                  innerWidth < width || innerHeight < height) {
                 // Fill the background.
@@ skipping 139 matching lines @@
 static SkImageDecoder_DecodeReg gReg(sk_libgif_dfactory);
 
 static SkImageDecoder::Format get_format_gif(SkStreamRewindable* stream) {
     if (is_gif(stream)) {
         return SkImageDecoder::kGIF_Format;
     }
     return SkImageDecoder::kUnknown_Format;
 }
 
 static SkImageDecoder_FormatReg gFormatReg(get_format_gif);