Update to current webrtc library

This is from the upstream library commit id
3326535126e435f1ba647885ce43a8f0f3d317eb, corresponding to Chromium
88.0.4290.1.

webrtc/modules/audio_processing/include/config.h

@@ -0,0 +1,131 @@
+/*
+ *  Copyright (c) 2013 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.
+ */
+
+#ifndef MODULES_AUDIO_PROCESSING_INCLUDE_CONFIG_H_
+#define MODULES_AUDIO_PROCESSING_INCLUDE_CONFIG_H_
+
+#include <map>
+
+#include "rtc_base/system/rtc_export.h"
+
+namespace webrtc {
+
+// Only add new values to the end of the enumeration and never remove (only
+// deprecate) to maintain binary compatibility.
+enum class ConfigOptionID {
+  kMyExperimentForTest,
+  kAlgo1CostFunctionForTest,
+  kTemporalLayersFactory,  // Deprecated
+  kNetEqCapacityConfig,    // Deprecated
+  kNetEqFastAccelerate,    // Deprecated
+  kVoicePacing,            // Deprecated
+  kExtendedFilter,         // Deprecated
+  kDelayAgnostic,          // Deprecated
+  kExperimentalAgc,
+  kExperimentalNs,
+  kBeamforming,               // Deprecated
+  kIntelligibility,           // Deprecated
+  kEchoCanceller3,            // Deprecated
+  kAecRefinedAdaptiveFilter,  // Deprecated
+  kLevelControl               // Deprecated
+};
+
+// Class Config is designed to ease passing a set of options across webrtc code.
+// Options are identified by typename in order to avoid incorrect casts.
+//
+// Usage:
+// * declaring an option:
+//    struct Algo1_CostFunction {
+//      virtual float cost(int x) const { return x; }
+//      virtual ~Algo1_CostFunction() {}
+//    };
+//
+// * accessing an option:
+//    config.Get<Algo1_CostFunction>().cost(value);
+//
+// * setting an option:
+//    struct SqrCost : Algo1_CostFunction {
+//      virtual float cost(int x) const { return x*x; }
+//    };
+//    config.Set<Algo1_CostFunction>(new SqrCost());
+//
+// Note: This class is thread-compatible (like STL containers).
+class RTC_EXPORT Config {
+ public:
+  // Returns the option if set or a default constructed one.
+  // Callers that access options too often are encouraged to cache the result.
+  // Returned references are owned by this.
+  //
+  // Requires std::is_default_constructible<T>
+  template <typename T>
+  const T& Get() const;
+
+  // Set the option, deleting any previous instance of the same.
+  // This instance gets ownership of the newly set value.
+  template <typename T>
+  void Set(T* value);
+
+  Config();
+  ~Config();
+
+ private:
+  struct BaseOption {
+    virtual ~BaseOption() {}
+  };
+
+  template <typename T>
+  struct Option : BaseOption {
+    explicit Option(T* v) : value(v) {}
+    ~Option() { delete value; }
+    T* value;
+  };
+
+  template <typename T>
+  static ConfigOptionID identifier() {
+    return T::identifier;
+  }
+
+  // Used to instantiate a default constructed object that doesn't needs to be
+  // owned. This allows Get<T> to be implemented without requiring explicitly
+  // locks.
+  template <typename T>
+  static const T& default_value() {
+    static const T* const def = new T();
+    return *def;
+  }
+
+  typedef std::map<ConfigOptionID, BaseOption*> OptionMap;
+  OptionMap options_;
+
+  Config(const Config&);
+  void operator=(const Config&);
+};
+
+template <typename T>
+const T& Config::Get() const {
+  OptionMap::const_iterator it = options_.find(identifier<T>());
+  if (it != options_.end()) {
+    const T* t = static_cast<Option<T>*>(it->second)->value;
+    if (t) {
+      return *t;
+    }
+  }
+  return default_value<T>();
+}
+
+template <typename T>
+void Config::Set(T* value) {
+  BaseOption*& it = options_[identifier<T>()];
+  delete it;
+  it = new Option<T>(value);
+}
+}  // namespace webrtc
+
+#endif  // MODULES_AUDIO_PROCESSING_INCLUDE_CONFIG_H_