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diff --git a/third_party/libwebrtc/rtc_base/experiments/struct_parameters_parser.h b/third_party/libwebrtc/rtc_base/experiments/struct_parameters_parser.h
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index 0000000000..f5f8340209
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+++ b/third_party/libwebrtc/rtc_base/experiments/struct_parameters_parser.h
@@ -0,0 +1,110 @@
+/*
+ *  Copyright (c) 2019 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 RTC_BASE_EXPERIMENTS_STRUCT_PARAMETERS_PARSER_H_
+#define RTC_BASE_EXPERIMENTS_STRUCT_PARAMETERS_PARSER_H_
+
+#include <functional>
+#include <map>
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
+
+#include "absl/memory/memory.h"
+#include "absl/strings/string_view.h"
+#include "absl/types/optional.h"
+#include "rtc_base/experiments/field_trial_parser.h"
+#include "rtc_base/experiments/field_trial_units.h"
+#include "rtc_base/string_encode.h"
+
+namespace webrtc {
+namespace struct_parser_impl {
+struct TypedMemberParser {
+ public:
+  bool (*parse)(absl::string_view src, void* target);
+  void (*encode)(const void* src, std::string* target);
+};
+
+struct MemberParameter {
+  const char* key;
+  void* member_ptr;
+  TypedMemberParser parser;
+};
+
+template <typename T>
+class TypedParser {
+ public:
+  static bool Parse(absl::string_view src, void* target);
+  static void Encode(const void* src, std::string* target);
+};
+
+// Instantiated in cc file to avoid duplication during compile. Add additional
+// parsers as needed. Generally, try to use these suggested types even if the
+// context where the value is used might require a different type. For instance,
+// a size_t representing a packet size should use an int parameter as there's no
+// need to support packet sizes larger than INT32_MAX.
+extern template class TypedParser<bool>;
+extern template class TypedParser<double>;
+extern template class TypedParser<int>;
+extern template class TypedParser<unsigned>;
+extern template class TypedParser<absl::optional<double>>;
+extern template class TypedParser<absl::optional<int>>;
+extern template class TypedParser<absl::optional<unsigned>>;
+
+extern template class TypedParser<DataRate>;
+extern template class TypedParser<DataSize>;
+extern template class TypedParser<TimeDelta>;
+extern template class TypedParser<absl::optional<DataRate>>;
+extern template class TypedParser<absl::optional<DataSize>>;
+extern template class TypedParser<absl::optional<TimeDelta>>;
+
+template <typename T>
+void AddMembers(MemberParameter* out, const char* key, T* member) {
+  *out = MemberParameter{
+      key, member,
+      TypedMemberParser{&TypedParser<T>::Parse, &TypedParser<T>::Encode}};
+}
+
+template <typename T, typename... Args>
+void AddMembers(MemberParameter* out,
+                const char* key,
+                T* member,
+                Args... args) {
+  AddMembers(out, key, member);
+  AddMembers(++out, args...);
+}
+}  // namespace struct_parser_impl
+
+class StructParametersParser {
+ public:
+  template <typename T, typename... Args>
+  static std::unique_ptr<StructParametersParser> Create(const char* first_key,
+                                                        T* first_member,
+                                                        Args... args) {
+    std::vector<struct_parser_impl::MemberParameter> members(
+        sizeof...(args) / 2 + 1);
+    struct_parser_impl::AddMembers(&members.front(), std::move(first_key),
+                                   first_member, args...);
+    return absl::WrapUnique(new StructParametersParser(std::move(members)));
+  }
+
+  void Parse(absl::string_view src);
+  std::string Encode() const;
+
+ private:
+  explicit StructParametersParser(
+      std::vector<struct_parser_impl::MemberParameter> members);
+
+  std::vector<struct_parser_impl::MemberParameter> members_;
+};
+
+}  // namespace webrtc
+
+#endif  // RTC_BASE_EXPERIMENTS_STRUCT_PARAMETERS_PARSER_H_