Replace RTC_DCHECK(false) with RTC_NOTREACHED().

webrtc/modules/audio_processing/gain_control_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 12 matching lines @@
 namespace {
 int16_t MapSetting(GainControl::Mode mode) {
   switch (mode) {
     case GainControl::kAdaptiveAnalog:
       return kAgcModeAdaptiveAnalog;
     case GainControl::kAdaptiveDigital:
       return kAgcModeAdaptiveDigital;
     case GainControl::kFixedDigital:
       return kAgcModeFixedDigital;
   }
-  RTC_DCHECK(false);
+  RTC_NOTREACHED();
   return -1;
 }
 
 }  // namespace
 
 class GainControlImpl::GainController {
  public:
   explicit GainController() {
     state_ = WebRtcAgc_Create();
     RTC_CHECK(state_);
@@ skipping 386 matching lines @@
   for (auto& gain_controller : gain_controllers_) {
     const int handle_error =
         WebRtcAgc_set_config(gain_controller->state(), config);
     if (handle_error != AudioProcessing::kNoError) {
       error = handle_error;
     }
   }
   return error;
 }
 }  // namespace webrtc