Make an enum class out of NetEqDecoder, and hide the neteq_decoders_ table

webrtc/modules/audio_coding/neteq/tools/neteq_quality_test.cc

 /*
  *  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.
  */
 
@@ skipping 190 matching lines @@
     }
     f = pow(x, units - 1) + a * x + b;
     iter ++;
   }
   return x;
 }
 
 NetEqQualityTest::NetEqQualityTest(int block_duration_ms,
                                    int in_sampling_khz,
                                    int out_sampling_khz,
-                                   enum NetEqDecoder decoder_type)
+                                   NetEqDecoder decoder_type)
     : decoder_type_(decoder_type),
       channels_(FLAGS_channels),
       decoded_time_ms_(0),
       decodable_time_ms_(0),
       drift_factor_(FLAGS_drift_factor),
       packet_loss_rate_(FLAGS_packet_loss_rate),
       block_duration_ms_(block_duration_ms),
       in_sampling_khz_(in_sampling_khz),
       out_sampling_khz_(out_sampling_khz),
       in_size_samples_(
@@ skipping 204 matching lines @@
     }
   }
   Log() << "Average bit rate was "
         << 8.0f * total_payload_size_bytes_ / FLAGS_runtime_ms
         << " kbps"
         << std::endl;
 }
 
 }  // namespace test
 }  // namespace webrtc