Copy pendingHeaderExtensions when cloning subclasses of RtpPacket.#2298

JonathanLennox merged 1 commit intojitsi:masterjitsi/jitsi-videobridge:masterfrom

JonathanLennox:clone-pending-header-extensionsJonathanLennox/jitsi-videobridge:clone-pending-header-extensionsCopy head branch name to clipboard