Switch SkAutoMalloc to SkAutoTMalloc to avoid cast

tests/ARGBImageEncoderTest.cpp

 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkImageEncoder.h"
 
 #include "SkBitmap.h"
 #include "SkCanvas.h"
 #include "SkStream.h"
+#include "SkTemplates.h"
 #include "Test.h"
 
 static SkColorType gColorTypes[] = {
     kRGB_565_SkColorType,
     kN32_SkColorType,
 };
 
 DEF_TEST(ARGBImageEncoder, reporter) {
     // Bytes we expect to get:
     const int kWidth = 3;
@@ skipping 19 matching lines @@
             SkCanvas canvas(bitmap);
             SkPaint paint;
             paint.setColor(SK_ColorRED);
             canvas.drawIRect(SkIRect::MakeLTRB(0, 0, kWidth, 1), paint);
             paint.setColor(SK_ColorGREEN);
             canvas.drawIRect(SkIRect::MakeLTRB(0, 1, kWidth, 2), paint);
         }
 
         // Transform the bitmap.
         int bufferSize = bitmap.width() * bitmap.height() * 4;
-        SkAutoMalloc pixelBufferManager(bufferSize);
-        char *pixelBuffer = static_cast<char *>(pixelBufferManager.get());
+        SkAutoTMalloc<char> pixelBufferManager(bufferSize);
+        char* pixelBuffer = pixelBufferManager.get();
         SkMemoryWStream out(pixelBuffer, bufferSize);
         REPORTER_ASSERT(reporter, enc->encodeStream(&out, bitmap, SkImageEncoder::kDefaultQuality));
 
         // Confirm we got the expected results.
         REPORTER_ASSERT(reporter, bufferSize == sizeof(comparisonBuffer));
         REPORTER_ASSERT(reporter, memcmp(pixelBuffer, comparisonBuffer, bufferSize) == 0);
     }
 }