Android: Enable C99 mode instead of C89 (default).

webrtc/modules/audio_coding/codecs/ilbc/nearest_neighbor.c

 /*
  *  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_NearestNeighbor.c
 
 ******************************************************************/
 
 #include "defines.h"
 
 void WebRtcIlbcfix_NearestNeighbor(size_t* index,
                                    const size_t* array,
                                    size_t value,
                                    size_t arlength) {
-  size_t i;
   size_t min_diff = (size_t)-1;
-  for (i = 0; i < arlength; i++) {
+  for (size_t i = 0; i < arlength; i++) {
     const size_t diff =
         (array[i] < value) ? (value - array[i]) : (array[i] - value);
     if (diff < min_diff) {
       *index = i;
       min_diff = diff;
     }
   }
 }