Get rid of leaks in SkCodec::NewFromStream.

src/codec/SkCodec_libbmp.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_libbmp.h"
 #include "SkCodecPriv.h"
 #include "SkColorPriv.h"
@@ skipping 90 matching lines @@
  */
 SkCodec* SkBmpCodec::NewFromIco(SkStream* stream) {
     return SkBmpCodec::NewFromStream(stream, true);
 }
 
 /*
  *
  * Read enough of the stream to initialize the SkBmpCodec. Returns a bool
  * representing success or failure. If it returned true, and codecOut was
  * not NULL, it will be set to a new SkBmpCodec.
+ * Does *not* take ownership of the passed in SkStream.
  *
  */
 bool SkBmpCodec::ReadHeader(SkStream* stream, bool isIco, SkCodec** codecOut) {
     // Header size constants
     static const uint32_t kBmpHeaderBytes = 14;
     static const uint32_t kBmpHeaderBytesPlusFour = kBmpHeaderBytes + 4;
     static const uint32_t kBmpOS2V1Bytes = 12;
     static const uint32_t kBmpOS2V2Bytes = 64;
     static const uint32_t kBmpInfoBaseBytes = 16;
     static const uint32_t kBmpInfoV1Bytes = 40;
@@ skipping 368 matching lines @@
     return true;
 }
 
 /*
  *
  * Creates a bmp decoder
  * Reads enough of the stream to determine the image format
  *
  */
 SkCodec* SkBmpCodec::NewFromStream(SkStream* stream, bool isIco) {
+    SkAutoTDelete<SkStream> streamDeleter(stream);
     SkCodec* codec = NULL;
     if (ReadHeader(stream, isIco, &codec)) {
+        // codec has taken ownership of stream, so we do not need to
+        // delete it.
+        SkASSERT(codec);
+        streamDeleter.detach();
         return codec;
     }
     return NULL;
 }
 
 /*
  *
  * Creates an instance of the decoder
  * Called only by NewFromStream
  *
@@ skipping 615 matching lines @@
                 uint32_t alphaBit =
                         (srcBuffer.get()[quotient] >> shift) & 0x1;
                 dstRow[x] &= alphaBit - 1;
             }
         }
     }
 
     // Finished decoding the entire image
     return kSuccess;
 }