ATTRIBUTE_UNUSED expanded to empty on MSVS, so be sure to use the variable.

Ideally, this is a stopgap fix until ATTRIBUTE_UNUSED can be given a
proper definition.

TBR=andrew@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/35409004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@7830 4adac7df-926f-26a2-2b94-8c16560cd09d
diff --git a/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.cc b/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.cc
index cf1d632..d6bc4b3 100644
--- a/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.cc
+++ b/webrtc/modules/audio_coding/codecs/ilbc/audio_encoder_ilbc.cc
@@ -55,9 +55,9 @@
                                       uint8_t* encoded,
                                       size_t* encoded_bytes,
                                       EncodedInfo* info) {
-  const size_t expected_output_len ATTRIBUTE_UNUSED =
+  const size_t expected_output_len =
       num_10ms_frames_per_packet_ == 2 ? 38 : 50;
-  DCHECK_GE(max_encoded_bytes, expected_output_len);
+  CHECK_GE(max_encoded_bytes, expected_output_len);
 
   // Save timestamp if starting a new packet.
   if (num_10ms_frames_buffered_ == 0)