Attempt to isolate a bug by adding a new CHECK

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 278 matching lines @@
 bool GainControlImpl::is_limiter_enabled() const {
   return limiter_enabled_;
 }
 
 int GainControlImpl::Initialize() {
   int err = ProcessingComponent::Initialize();
   if (err != apm_->kNoError || !is_component_enabled()) {
     return err;
   }
 
-  capture_levels_.assign(num_handles(), analog_capture_level_);
+  const int n = num_handles();
+  RTC_CHECK_GE(n, 0) << "Bad number of handles: " << n;
+  capture_levels_.assign(n, analog_capture_level_);
   return apm_->kNoError;
 }
 
 void* GainControlImpl::CreateHandle() const {
   return WebRtcAgc_Create();
 }
 
 void GainControlImpl::DestroyHandle(void* handle) const {
   WebRtcAgc_Free(static_cast<Handle*>(handle));
 }
@@ skipping 24 matching lines @@
   return apm_->num_output_channels();
 }
 
 int GainControlImpl::GetHandleError(void* handle) const {
   // The AGC has no get_error() function.
   // (Despite listing errors in its interface...)
   assert(handle != NULL);
   return apm_->kUnspecifiedError;
 }
 }  // namespace webrtc