Revert of Introduced new scheme for controlling the functionality inside the audio processing module

webrtc/modules/audio_processing/level_controller/level_controller.cc

 /*
  *  Copyright (c) 2016 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.
  */
 
@@ skipping 244 matching lines @@
 
   data_dumper_->DumpRaw("lc_selected_gain", 1, &last_gain_);
   data_dumper_->DumpRaw("lc_noise_energy", 1, &noise_energy);
   data_dumper_->DumpRaw("lc_peak_level", 1, &long_term_peak_level);
   data_dumper_->DumpRaw("lc_saturating_gain", 1, &saturating_gain);
 
   data_dumper_->DumpWav("lc_output", audio->num_frames(),
                         audio->channels_f()[0], *sample_rate_hz_, 1);
 }
 
-std::string LevelController::ToString(
-    const AudioProcessing::Config::LevelController& config) {
-  std::stringstream ss;
-  ss << "{"
-     << "enabled: " << (config.enabled ? "true" : "false") << "}";
-  return ss.str();
-}
-
-bool LevelController::Validate(
-    const AudioProcessing::Config::LevelController& config) {
-  return true;
-}
-
 }  // namespace webrtc