Remove old methods in AudioTransport, make it pass a gn build

webrtc/modules/audio_device/audio_device.gypi

 # Copyright (c) 2012 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 21 matching lines @@
       },
       # TODO(xians): Rename files to e.g. *_linux.{ext}, remove sources in conditions section
       'sources': [
         'include/audio_device.h',
         'include/audio_device_defines.h',
         'audio_device_buffer.cc',
         'audio_device_buffer.h',
         'audio_device_generic.cc',
         'audio_device_generic.h',
         'audio_device_config.h',
+        'audio_transport.cc',
         'dummy/audio_device_dummy.cc',
         'dummy/audio_device_dummy.h',
         'dummy/file_audio_device.cc',
         'dummy/file_audio_device.h',
         'fine_audio_buffer.cc',
         'fine_audio_buffer.h',
       ],
       'conditions': [
         ['OS=="linux"', {
           'include_dirs': [
@@ skipping 233 matching lines @@
             'test/audio_device_test_defines.h',
             'test/func_test_manager.cc',
             'test/func_test_manager.h',
           ],
         },
       ], # targets
     }], # include_tests==1 and OS!=ios
   ],
 }