Remove ACMCodecDB::Codec, and make the rest of ACMCodecDB private

webrtc/modules/audio_coding/main/acm2/rent_a_codec.h

 /*
  *  Copyright (c) 2015 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 130 matching lines @@
     return static_cast<size_t>(codec_index) < NumberOfCodecs()
                ? rtc::Maybe<RentACodec::CodecId>(
                      static_cast<RentACodec::CodecId>(codec_index))
                : rtc::Maybe<RentACodec::CodecId>();
   }
 
   static rtc::Maybe<CodecId> CodecIdByParams(const char* payload_name,
                                              int sampling_freq_hz,
                                              int channels);
   static rtc::Maybe<CodecInst> CodecInstById(CodecId codec_id);
+  static rtc::Maybe<CodecId> CodecIdByInst(const CodecInst& codec_inst);
   static rtc::Maybe<CodecInst> CodecInstByParams(const char* payload_name,
                                                  int sampling_freq_hz,
                                                  int channels);
   static bool IsCodecValid(const CodecInst& codec_inst);
 
   static inline bool IsPayloadTypeValid(int payload_type) {
     return payload_type >= 0 && payload_type <= 127;
   }
 
   static rtc::ArrayView<const CodecInst> Database();
 
   static rtc::Maybe<bool> IsSupportedNumChannels(CodecId codec_id,
                                                  int num_channels);
 
   static rtc::Maybe<NetEqDecoder> NetEqDecoderFromCodecId(CodecId codec_id,
                                                           int num_channels);
 };
 
 }  // namespace acm2
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_CODING_MAIN_ACM2_RENT_A_CODEC_H_