AGC: Route clipping parameter from webrtc::Config to AGC

webrtc/modules/audio_processing/include/audio_processing.h

 /*
  *  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 96 matching lines @@
 // AGC moves the microphone volume up to |startup_min_volume| if the current
 // microphone volume is set too low. The value is clamped to its operating range
 // [12, 255]. Here, 255 maps to 100%.
 //
 // Must be provided through AudioProcessing::Create(Confg&).
 #if defined(WEBRTC_CHROMIUM_BUILD)
 static const int kAgcStartupMinVolume = 85;
 #else
 static const int kAgcStartupMinVolume = 0;
 #endif  // defined(WEBRTC_CHROMIUM_BUILD)
+static constexpr int kClippedLevelMin = 170;
 struct ExperimentalAgc {
-  ExperimentalAgc() : enabled(true), startup_min_volume(kAgcStartupMinVolume) {}
-  explicit ExperimentalAgc(bool enabled)
-      : enabled(enabled), startup_min_volume(kAgcStartupMinVolume) {}
+  ExperimentalAgc() = default;
+  explicit ExperimentalAgc(bool enabled) : enabled(enabled) {}
   ExperimentalAgc(bool enabled, int startup_min_volume)
       : enabled(enabled), startup_min_volume(startup_min_volume) {}
+  ExperimentalAgc(bool enabled, int startup_min_volume, int clipped_level_min)
+      : enabled(enabled),
+        startup_min_volume(startup_min_volume),
+        clipped_level_min(clipped_level_min) {}
   static const ConfigOptionID identifier = ConfigOptionID::kExperimentalAgc;
-  bool enabled;
-  int startup_min_volume;
+  bool enabled = true;
+  int startup_min_volume = kAgcStartupMinVolume;
+  // Lowest microphone level that will be applied in response to clipping.
+  int clipped_level_min = kClippedLevelMin;
 };
 
 // Use to enable experimental noise suppression. It can be set in the
 // constructor or using AudioProcessing::SetExtraOptions().
 struct ExperimentalNs {
   ExperimentalNs() : enabled(false) {}
   explicit ExperimentalNs(bool enabled) : enabled(enabled) {}
   static const ConfigOptionID identifier = ConfigOptionID::kExperimentalNs;
   bool enabled;
 };
@@ skipping 939 matching lines @@
   // This does not impact the size of frames passed to |ProcessStream()|.
   virtual int set_frame_size_ms(int size) = 0;
   virtual int frame_size_ms() const = 0;
 
  protected:
   virtual ~VoiceDetection() {}
 };
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_PROCESSING_INCLUDE_AUDIO_PROCESSING_H_