Add an active ICE controller factory to IceTransportInit (#3/n)

P2PTransportChannel can then use either of the ICE controller factories configured with field trials.

Bug: webrtc:14367, webrtc:14131
Change-Id: I09ab99673d6ef81f56abe88987f5b67d84c24cb5
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/271292
Reviewed-by: Jonas Oreland <jonaso@webrtc.org>
Reviewed-by: Per Kjellander <perkj@webrtc.org>
Commit-Queue: Sameer Vijaykar <samvi@google.com>
Cr-Commit-Position: refs/heads/main@{#38076}

api/ice_transport_interface.h

@@ -24,6 +24,7 @@ namespace cricket {
 class IceTransportInternal;
 class PortAllocator;
 class IceControllerFactoryInterface;
+class ActiveIceControllerFactoryInterface;
 }  // namespace cricket
 
 namespace webrtc {
@@ -84,6 +85,21 @@ struct IceTransportInit final {
     return ice_controller_factory_;
   }
 
+  // An active ICE controller actively manages the connection used by an ICE
+  // transport, in contrast with a legacy ICE controller that only picks the
+  // best connection to use or ping, and lets the transport decide when and
+  // whether to switch.
+  // TODO(bugs.webrtc.org/14367): currently unused, update doc when used.
+  void set_active_ice_controller_factory(
+      cricket::ActiveIceControllerFactoryInterface*
+          active_ice_controller_factory) {
+    active_ice_controller_factory_ = active_ice_controller_factory;
+  }
+  cricket::ActiveIceControllerFactoryInterface*
+  active_ice_controller_factory() {
+    return active_ice_controller_factory_;
+  }
+
   const FieldTrialsView* field_trials() { return field_trials_; }
   void set_field_trials(const FieldTrialsView* field_trials) {
     field_trials_ = field_trials;
@@ -96,6 +112,8 @@ struct IceTransportInit final {
   AsyncResolverFactory* async_resolver_factory_ = nullptr;
   RtcEventLog* event_log_ = nullptr;
   cricket::IceControllerFactoryInterface* ice_controller_factory_ = nullptr;
+  cricket::ActiveIceControllerFactoryInterface* active_ice_controller_factory_ =
+      nullptr;
   const FieldTrialsView* field_trials_ = nullptr;
   // TODO(https://crbug.com/webrtc/12657): Redesign to have const members.
 };

p2p/BUILD.gn

@@ -18,6 +18,7 @@ group("p2p") {
 rtc_library("rtc_p2p") {
   visibility = [ "*" ]
   sources = [
+    "base/active_ice_controller_factory_interface.h",
     "base/active_ice_controller_interface.h",
     "base/async_stun_tcp_socket.cc",
     "base/async_stun_tcp_socket.h",

p2p/base/active_ice_controller_factory_interface.h

@@ -0,0 +1,39 @@
+/*
+ *  Copyright 2022 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 P2P_BASE_ACTIVE_ICE_CONTROLLER_FACTORY_INTERFACE_H_
+#define P2P_BASE_ACTIVE_ICE_CONTROLLER_FACTORY_INTERFACE_H_
+
+#include <memory>
+
+#include "p2p/base/active_ice_controller_interface.h"
+#include "p2p/base/ice_agent_interface.h"
+#include "p2p/base/ice_controller_factory_interface.h"
+
+namespace cricket {
+
+// An active ICE controller may be constructed with the same arguments as a
+// legacy ICE controller. Additionally, an ICE agent must be provided for the
+// active ICE controller to interact with.
+struct ActiveIceControllerFactoryArgs {
+  IceControllerFactoryArgs legacy_args;
+  IceAgentInterface* ice_agent;
+};
+
+class ActiveIceControllerFactoryInterface {
+ public:
+  virtual ~ActiveIceControllerFactoryInterface() = default;
+  virtual std::unique_ptr<ActiveIceControllerInterface> Create(
+      const ActiveIceControllerFactoryArgs&) = 0;
+};
+
+}  // namespace cricket
+
+#endif  // P2P_BASE_ACTIVE_ICE_CONTROLLER_FACTORY_INTERFACE_H_