Limit the max volume to 255 before pass it to APM.

content/renderer/media/media_stream_audio_processor.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/renderer/media/media_stream_audio_processor.h"
 
 #include "base/command_line.h"
 #include "base/debug/trace_event.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
 #include "content/public/common/content_switches.h"
 #include "content/renderer/media/media_stream_audio_processor_options.h"
 #include "content/renderer/media/rtc_media_constraints.h"
+#include "content/renderer/media/webrtc_audio_device_impl.h"
 #include "media/audio/audio_parameters.h"
 #include "media/base/audio_converter.h"
 #include "media/base/audio_fifo.h"
 #include "media/base/channel_layout.h"
 #include "third_party/WebKit/public/platform/WebMediaConstraints.h"
 #include "third_party/libjingle/source/talk/app/webrtc/mediaconstraintsinterface.h"
 #include "third_party/webrtc/modules/audio_processing/typing_detection.h"
 
 namespace content {
 
@@ skipping 443 matching lines @@
   DCHECK_LT(capture_delay_ms,
             std::numeric_limits<base::subtle::Atomic32>::max());
   int total_delay_ms =  capture_delay_ms + render_delay_ms;
   if (total_delay_ms > 300) {
     LOG(WARNING) << "Large audio delay, capture delay: " << capture_delay_ms
                  << "ms; render delay: " << render_delay_ms << "ms";
   }
 
   audio_processing_->set_stream_delay_ms(total_delay_ms);
 
+  DCHECK_LE(volume, WebRtcAudioDeviceImpl::kMaxVolumeLevel);
   webrtc::GainControl* agc = audio_processing_->gain_control();
   int err = agc->set_stream_analog_level(volume);
   DCHECK_EQ(err, 0) << "set_stream_analog_level() error: " << err;
 
   audio_processing_->set_stream_key_pressed(key_pressed);
 
   err = audio_processing_->ProcessStream(audio_frame);
   DCHECK_EQ(err, 0) << "ProcessStream() error: " << err;
 
   if (typing_detector_ &&
@@ skipping 23 matching lines @@
 }
 
 bool MediaStreamAudioProcessor::IsAudioTrackProcessingEnabled() const {
   const std::string group_name =
       base::FieldTrialList::FindFullName("MediaStreamAudioTrackProcessing");
   return group_name == "Enabled" || CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kEnableAudioTrackProcessing);
 }
 
 }  // namespace content