WebRtcIlbcfix_EnhancerInterface: Let input array be const

webrtc/modules/audio_coding/codecs/ilbc/enhancer_interface.h

 /*
  *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE 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.
  */
 
 /******************************************************************
 
  iLBC Speech Coder ANSI-C Source Code
 
  WebRtcIlbcfix_EnhancerInterface.h
 
 ******************************************************************/
 
 #ifndef WEBRTC_MODULES_AUDIO_CODING_CODECS_ILBC_MAIN_SOURCE_ENHANCER_INTERFACE_H_
 #define WEBRTC_MODULES_AUDIO_CODING_CODECS_ILBC_MAIN_SOURCE_ENHANCER_INTERFACE_H_
 
 #include "defines.h"
 
 /*----------------------------------------------------------------*
  * interface for enhancer
  *---------------------------------------------------------------*/
 
-size_t WebRtcIlbcfix_EnhancerInterface( /* (o) Estimated lag in end of in[] */
-    int16_t *out,     /* (o) enhanced signal */
-    int16_t *in,      /* (i) unenhanced signal */
-    IlbcDecoder *iLBCdec_inst /* (i) buffers etc */
-                                        );
+size_t  // (o) Estimated lag in end of in[]
+    WebRtcIlbcfix_EnhancerInterface(
+        int16_t* out,                // (o) enhanced signal
+        const int16_t* in,           // (i) unenhanced signal
+        IlbcDecoder* iLBCdec_inst);  // (i) buffers etc
 
 #endif