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diff --git a/third_party/libwebrtc/call/adaptation/broadcast_resource_listener.h b/third_party/libwebrtc/call/adaptation/broadcast_resource_listener.h
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+/*
+ *  Copyright 2020 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 CALL_ADAPTATION_BROADCAST_RESOURCE_LISTENER_H_
+#define CALL_ADAPTATION_BROADCAST_RESOURCE_LISTENER_H_
+
+#include <vector>
+
+#include "api/adaptation/resource.h"
+#include "api/scoped_refptr.h"
+#include "rtc_base/synchronization/mutex.h"
+
+namespace webrtc {
+
+// Responsible for forwarding 1 resource usage measurement to N listeners by
+// creating N "adapter" resources.
+//
+// Example:
+// If we have ResourceA, ResourceListenerX and ResourceListenerY we can create a
+// BroadcastResourceListener that listens to ResourceA, use CreateAdapter() to
+// spawn adapter resources ResourceX and ResourceY and let ResourceListenerX
+// listen to ResourceX and ResourceListenerY listen to ResourceY. When ResourceA
+// makes a measurement it will be echoed by both ResourceX and ResourceY.
+//
+// TODO(https://crbug.com/webrtc/11565): When the ResourceAdaptationProcessor is
+// moved to call there will only be one ResourceAdaptationProcessor that needs
+// to listen to the injected resources. When this is the case, delete this class
+// and DCHECK that a Resource's listener is never overwritten.
+class BroadcastResourceListener : public ResourceListener {
+ public:
+  explicit BroadcastResourceListener(
+      rtc::scoped_refptr<Resource> source_resource);
+  ~BroadcastResourceListener() override;
+
+  rtc::scoped_refptr<Resource> SourceResource() const;
+  void StartListening();
+  void StopListening();
+
+  // Creates a Resource that redirects any resource usage measurements that
+  // BroadcastResourceListener receives to its listener.
+  rtc::scoped_refptr<Resource> CreateAdapterResource();
+
+  // Unregister the adapter from the BroadcastResourceListener; it will no
+  // longer receive resource usage measurement and will no longer be referenced.
+  // Use this to prevent memory leaks of old adapters.
+  void RemoveAdapterResource(rtc::scoped_refptr<Resource> resource);
+  std::vector<rtc::scoped_refptr<Resource>> GetAdapterResources();
+
+  // ResourceListener implementation.
+  void OnResourceUsageStateMeasured(rtc::scoped_refptr<Resource> resource,
+                                    ResourceUsageState usage_state) override;
+
+ private:
+  class AdapterResource;
+  friend class AdapterResource;
+
+  const rtc::scoped_refptr<Resource> source_resource_;
+  Mutex lock_;
+  bool is_listening_ RTC_GUARDED_BY(lock_);
+  // The AdapterResource unregisters itself prior to destruction, guaranteeing
+  // that these pointers are safe to use.
+  std::vector<rtc::scoped_refptr<AdapterResource>> adapters_
+      RTC_GUARDED_BY(lock_);
+};
+
+}  // namespace webrtc
+
+#endif  // CALL_ADAPTATION_BROADCAST_RESOURCE_LISTENER_H_