Get rid of leaks in SkCodec::NewFromStream.

src/codec/SkCodec.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 "SkCodec.h"
 #include "SkData.h"
 #include "SkCodec_libbmp.h"
@@ skipping 14 matching lines @@
     { SkGifCodec::IsGif, SkGifCodec::NewFromStream },
     { SkIcoCodec::IsIco, SkIcoCodec::NewFromStream },
     { SkBmpCodec::IsBmp, SkBmpCodec::NewFromStream },
     { SkWbmpCodec::IsWbmp, SkWbmpCodec::NewFromStream }
 };
 
 SkCodec* SkCodec::NewFromStream(SkStream* stream) {
     if (!stream) {
         return NULL;
     }
+
+    SkAutoTDelete<SkStream> streamDeleter(stream);
     
-    SkCodec* codec = NULL;
+    SkAutoTDelete<SkCodec> codec(NULL);
     for (uint32_t i = 0; i < SK_ARRAY_COUNT(gDecoderProcs); i++) {
         DecoderProc proc = gDecoderProcs[i];
         const bool correctFormat = proc.IsFormat(stream);
         if (!stream->rewind()) {
             return NULL;
         }
         if (correctFormat) {
-            codec = proc.NewFromStream(stream);
+            codec.reset(proc.NewFromStream(streamDeleter.detach()));
             break;
         }
     }
 
     // Set the max size at 128 megapixels (512 MB for kN32).
     // This is about 4x smaller than a test image that takes a few minutes for
     // dm to decode and draw.
     const int32_t maxSize = 1 << 27;
-    if (codec != NULL &&
-            codec->getInfo().width() * codec->getInfo().height() > maxSize) {
+    if (codec && codec->getInfo().width() * codec->getInfo().height() > maxSize) {
         SkCodecPrintf("Error: Image size too large, cannot decode.\n");
         return NULL;
     } else {
-        return codec;
+        return codec.detach();
     }
 }
 
 SkCodec* SkCodec::NewFromData(SkData* data) {
     if (!data) {
         return NULL;
     }
     return NewFromStream(SkNEW_ARGS(SkMemoryStream, (data)));
 }
 
@@ skipping 15 matching lines @@
         return kNoRewindNecessary_RewindState;
     }
     return fStream->rewind() ? kRewound_RewindState
                              : kCouldNotRewind_RewindState;
 }
 
 SkScanlineDecoder* SkCodec::getScanlineDecoder(const SkImageInfo& dstInfo) {
     fScanlineDecoder.reset(this->onGetScanlineDecoder(dstInfo));
     return fScanlineDecoder.get();
 }