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

webrtc/modules/audio_processing/include/audio_processing.h

Index: webrtc/modules/audio_processing/include/audio_processing.h
diff --git a/webrtc/modules/audio_processing/include/audio_processing.h b/webrtc/modules/audio_processing/include/audio_processing.h
index d3ae3e8a6a964a913e05a9cb45fa67504eb84e10..d03c7f4ab4f336189a335f0740ab358808ddf7f6 100644
--- a/webrtc/modules/audio_processing/include/audio_processing.h
+++ b/webrtc/modules/audio_processing/include/audio_processing.h
@@ -114,15 +114,21 @@ 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