Remove additional channel constraints when Beamforming is enabled in AudioProcessing

webrtc/modules/audio_processing/echo_cancellation_impl.cc

 /*
  *  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 156 matching lines @@
 
   if (!apm_->was_stream_delay_set()) {
     return AudioProcessing::kStreamParameterNotSetError;
   }
 
   if (drift_compensation_enabled_ && !was_stream_drift_set_) {
     return AudioProcessing::kStreamParameterNotSetError;
   }
 
   assert(audio->num_frames_per_band() <= 160);
-  assert(audio->num_channels() == apm_->num_output_channels());
+  assert(audio->num_channels() == apm_->num_proc_channels());
 
   int err = AudioProcessing::kNoError;
 
   // The ordering convention must be followed to pass to the correct AEC.
   size_t handle_index = 0;
   stream_has_echo_ = false;
   for (int i = 0; i < audio->num_channels(); i++) {
     for (int j = 0; j < apm_->num_reverse_channels(); j++) {
       Handle* my_handle = handle(handle_index);
       err = WebRtcAec_Process(my_handle, audio->split_bands_const_f(i),
@@ skipping 305 matching lines @@
   // Not locked as it only relies on APM public API which is threadsafe.
   return apm_->num_output_channels() * apm_->num_reverse_channels();
 }
 
 int EchoCancellationImpl::GetHandleError(void* handle) const {
   // Not locked as it does not rely on anything in the state.
   assert(handle != NULL);
   return AudioProcessing::kUnspecifiedError;
 }
 }  // namespace webrtc