libwebp: update to 0.4.2-rc2

third_party/libwebp/dec/idec.c

 // Copyright 2011 Google Inc. All Rights Reserved.
 //
 // Use of this source code is governed by a BSD-style license
 // that can be found in the COPYING file in the root of the source
 // tree. An additional intellectual property rights grant can be found
 // in the file PATENTS. All contributing project authors may
 // be found in the AUTHORS file in the root of the source tree.
 // -----------------------------------------------------------------------------
 //
 // Incremental decoding
@@ skipping 511 matching lines @@
   const size_t curr_size = MemDataSize(&idec->mem_);
   assert(idec->is_lossless_);
 
   // At present Lossless decoder can't decode image incrementally. So wait till
   // all the image data is aggregated before image can be decoded.
   if (curr_size < idec->chunk_size_) {
     return VP8_STATUS_SUSPENDED;
   }
 
   if (!VP8LDecodeImage(dec)) {
+    // The decoding is called after all the data-bytes are aggregated. Change
+    // the error to VP8_BITSTREAM_ERROR in case lossless decoder fails to decode
+    // all the pixels (VP8_STATUS_SUSPENDED).
+    if (dec->status_ == VP8_STATUS_SUSPENDED) {
+      dec->status_ = VP8_STATUS_BITSTREAM_ERROR;
+    }
     return ErrorStatusLossless(idec, dec->status_);
   }
 
   return FinishDecoding(idec);
 }
 
   // Main decoding loop
 static VP8StatusCode IDecode(WebPIDecoder* idec) {
   VP8StatusCode status = VP8_STATUS_SUSPENDED;
 
@@ skipping 300 matching lines @@
   }
 
   idec->io_.put = put;
   idec->io_.setup = setup;
   idec->io_.teardown = teardown;
   idec->io_.opaque = user_data;
 
   return 1;
 }