Revert of Drop the 16kHz sample rate restriction on AECM and zero out higher bands

webrtc/modules/audio_processing/include/audio_processing.h

 /*
  *  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.
  */
 
@@ skipping 490 matching lines @@
   enum NativeRate {
     kSampleRate8kHz = 8000,
     kSampleRate16kHz = 16000,
     kSampleRate32kHz = 32000,
     kSampleRate48kHz = 48000
   };
 
   static const int kNativeSampleRatesHz[];
   static const size_t kNumNativeSampleRates;
   static const int kMaxNativeSampleRateHz;
+  static const int kMaxAECMSampleRateHz;
 
   static const int kChunkSizeMs = 10;
 };
 
 class StreamConfig {
  public:
   // sample_rate_hz: The sampling rate of the stream.
   //
   // num_channels: The number of audio channels in the stream, excluding the
   //               keyboard channel if it is present. When passing a
@@ skipping 456 matching lines @@
   // This does not impact the size of frames passed to |ProcessStream()|.
   virtual int set_frame_size_ms(int size) = 0;
   virtual int frame_size_ms() const = 0;
 
  protected:
   virtual ~VoiceDetection() {}
 };
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_INCLUDE_AUDIO_PROCESSING_H_