Reland: Drop the 16kHz sample rate restriction on AECM and zero out higher bands

webrtc/modules/audio_processing/echo_control_mobile_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 225 matching lines @@
       err = WebRtcAecm_Process(cancellers_[handle_index]->state(), noisy, clean,
                                audio->split_bands(capture)[kBand0To8kHz],
                                audio->num_frames_per_band(), stream_delay_ms);
 
       if (err != AudioProcessing::kNoError) {
         return MapError(err);
       }
 
       ++handle_index;
     }
+    for (size_t band = 1u; band < audio->num_bands(); ++band) {
+      memset(audio->split_bands(capture)[band],
+             0,
+             audio->num_frames_per_band() *
+                 sizeof(audio->split_bands(capture)[band][0]));
+    }
   }
   return AudioProcessing::kNoError;
 }
 
 int EchoControlMobileImpl::Enable(bool enable) {
   // Ensure AEC and AECM are not both enabled.
   rtc::CritScope cs_render(crit_render_);
   rtc::CritScope cs_capture(crit_capture_);
   RTC_DCHECK(stream_properties_);
 
@@ skipping 177 matching lines @@
   }
   return error;
 }
 
 size_t EchoControlMobileImpl::num_handles_required() const {
   RTC_DCHECK(stream_properties_);
   return stream_properties_->num_output_channels *
          stream_properties_->num_reverse_channels;
 }
 }  // namespace webrtc