Only destroy huffman if build succeeded.

src/images/SkImageDecoder_libjpeg.cpp

Index: src/images/SkImageDecoder_libjpeg.cpp
diff --git a/src/images/SkImageDecoder_libjpeg.cpp b/src/images/SkImageDecoder_libjpeg.cpp
index 788e3526d2d9880e62fcb9a8a612e6262765425e..2bd48186ac5079431bd5c7832d40c99e6d884ee6 100644
--- a/src/images/SkImageDecoder_libjpeg.cpp
+++ b/src/images/SkImageDecoder_libjpeg.cpp
@@ -143,9 +143,9 @@ public:
         SkASSERT(fReadHeaderSucceeded);
         SkASSERT(!fHuffmanCreated);
         jpeg_create_huffman_index(&fCInfo, &fHuffmanIndex);
-        fHuffmanCreated = true;
         SkASSERT(1 == fCInfo.scale_num && 1 == fCInfo.scale_denom);
-        return jpeg_build_huffman_index(&fCInfo, &fHuffmanIndex);
+        fHuffmanCreated = jpeg_build_huffman_index(&fCInfo, &fHuffmanIndex);
+        return fHuffmanCreated;
     }
 
     /**