Moved legacy_encoded_audio_frame into audio_decoder_interface.

webrtc/modules/audio_coding/codecs/interfaces.gypi

 # Copyright (c) 2014 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': [
     {
       'target_name': 'audio_decoder_interface',
       'type': 'static_library',
       'sources': [
         'audio_decoder.cc',
         'audio_decoder.h',
+        'legacy_encoded_audio_frame.cc',
+        'legacy_encoded_audio_frame.h',
       ],
       'dependencies': [
         '<(webrtc_root)/base/base.gyp:rtc_base_approved',
         '<(webrtc_root)/common.gyp:webrtc_common',
       ],
     },
 
     {
       'target_name': 'audio_encoder_interface',
       'type': 'static_library',
       'sources': [
         'audio_encoder.cc',
         'audio_encoder.h',
       ],
       'dependencies': [
         '<(webrtc_root)/base/base.gyp:rtc_base_approved',
         '<(webrtc_root)/common.gyp:webrtc_common',
       ],
     },
   ],
 }