Move AudioDecoderIsac* to its own files

webrtc/modules/audio_coding/codecs/isac/isac.gypi

 # 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.
 
 {
   'targets': [
@@ skipping 10 matching lines @@
         'main/interface',
         '<(webrtc_root)',
       ],
       'direct_dependent_settings': {
         'include_dirs': [
           'main/interface',
           '<(webrtc_root)',
         ],
       },
       'sources': [
+        'main/interface/audio_decoder_isac.h',
         'main/interface/audio_encoder_isac.h',
         'main/interface/isac.h',
         'main/source/arith_routines.c',
         'main/source/arith_routines_hist.c',
         'main/source/arith_routines_logist.c',
+        'main/source/audio_decoder_isac.cc',
         'main/source/audio_encoder_isac.cc',
         'main/source/bandwidth_estimator.c',
         'main/source/crc.c',
         'main/source/decode.c',
         'main/source/decode_bwe.c',
         'main/source/encode.c',
         'main/source/encode_lpc_swb.c',
         'main/source/entropy_coding.c',
         'main/source/fft.c',
         'main/source/filter_functions.c',
         'main/source/filterbank_tables.c',
         'main/source/intialize.c',
         'main/source/isac.c',
+        'main/source/isac_float_type.h',
         'main/source/filterbanks.c',
         'main/source/pitch_lag_tables.c',
         'main/source/lattice.c',
         'main/source/lpc_gain_swb_tables.c',
         'main/source/lpc_analysis.c',
         'main/source/lpc_shape_swb12_tables.c',
         'main/source/lpc_shape_swb16_tables.c',
         'main/source/lpc_tables.c',
         'main/source/pitch_estimator.c',
         'main/source/pitch_filter.c',
@@ skipping 24 matching lines @@
      'conditions': [
        ['OS=="linux"', {
          'link_settings': {
            'libraries': ['-lm',],
          },
        }],
      ],
     },
   ],
 }