Reland "Move injection of PacketSocketFactory from PC to PCF"

This is a reland of commit 905c3a6c73d293882ef11942066ccda52a9e14d1

Change from previous attempt is between ps#1 and ps#2: Use PeerConnectionFactoryInterface::Options to clear the `network_ignore_mask`.

Original change's description:
> Move injection of PacketSocketFactory from PC to PCF
>
> Injection via PeerConnectionDependecies was broken, in not accepting
> ownership of the injected object.
>
> Bug: webrtc:7447, webrtc:14204
> Change-Id: Ic53f05d51928b006fc1e46d502633d88471eb518
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/266140
> Reviewed-by: Harald Alvestrand <hta@webrtc.org>
> Commit-Queue: Niels Moller <nisse@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#37270}

Bug: webrtc:7447, webrtc:14204
Change-Id: Ic78ebec2e88a8c44699015c8c7a44e137f44253a
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/265982
Reviewed-by: Harald Alvestrand <hta@webrtc.org>
Commit-Queue: Niels Moller <nisse@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#37290}
diff --git a/api/BUILD.gn b/api/BUILD.gn
index 5f6bc49..cd1c104 100644
--- a/api/BUILD.gn
+++ b/api/BUILD.gn
@@ -1100,6 +1100,17 @@
     ]
   }
 
+  rtc_source_set("mock_packet_socket_factory") {
+    visibility = [ "*" ]
+    testonly = true
+    sources = [ "test/mock_packet_socket_factory.h" ]
+
+    deps = [
+      ":packet_socket_factory",
+      "../test:test_support",
+    ]
+  }
+
   rtc_source_set("mock_peerconnectioninterface") {
     visibility = [ "*" ]
     testonly = true
@@ -1322,6 +1333,7 @@
       ":mock_frame_decryptor",
       ":mock_frame_encryptor",
       ":mock_media_stream_interface",
+      ":mock_packet_socket_factory",
       ":mock_peer_connection_factory_interface",
       ":mock_peerconnectioninterface",
       ":mock_rtp",
diff --git a/api/peer_connection_interface.h b/api/peer_connection_interface.h
index 3e70855..8a6ae96 100644
--- a/api/peer_connection_interface.h
+++ b/api/peer_connection_interface.h
@@ -1379,10 +1379,9 @@
   PeerConnectionObserver* observer = nullptr;
   // Optional dependencies
   // TODO(bugs.webrtc.org/7447): remove port allocator once downstream is
-  // updated. For now, you can only set one of allocator and
-  // packet_socket_factory, not both.
+  // updated. The recommended way to inject networking components is to pass a
+  // PacketSocketFactory when creating the PeerConnectionFactory.
   std::unique_ptr<cricket::PortAllocator> allocator;
-  std::unique_ptr<rtc::PacketSocketFactory> packet_socket_factory;
   // Factory for creating resolvers that look up hostnames in DNS
   std::unique_ptr<webrtc::AsyncDnsResolverFactoryInterface>
       async_dns_resolver_factory;
@@ -1422,6 +1421,7 @@
   rtc::Thread* worker_thread = nullptr;
   rtc::Thread* signaling_thread = nullptr;
   rtc::SocketFactory* socket_factory = nullptr;
+  std::unique_ptr<rtc::PacketSocketFactory> packet_socket_factory;
   std::unique_ptr<TaskQueueFactory> task_queue_factory;
   std::unique_ptr<cricket::MediaEngineInterface> media_engine;
   std::unique_ptr<CallFactoryInterface> call_factory;
diff --git a/api/test/mock_packet_socket_factory.h b/api/test/mock_packet_socket_factory.h
new file mode 100644
index 0000000..7e59556
--- /dev/null
+++ b/api/test/mock_packet_socket_factory.h
@@ -0,0 +1,49 @@
+/*
+ *  Copyright (c) 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 API_TEST_MOCK_PACKET_SOCKET_FACTORY_H_
+#define API_TEST_MOCK_PACKET_SOCKET_FACTORY_H_
+
+#include <memory>
+#include <string>
+
+#include "api/packet_socket_factory.h"
+#include "test/gmock.h"
+
+namespace rtc {
+class MockPacketSocketFactory : public PacketSocketFactory {
+ public:
+  MOCK_METHOD(AsyncPacketSocket*,
+              CreateUdpSocket,
+              (const SocketAddress&, uint16_t, uint16_t),
+              (override));
+  MOCK_METHOD(AsyncListenSocket*,
+              CreateServerTcpSocket,
+              (const SocketAddress&, uint16_t, uint16_t, int opts),
+              (override));
+  MOCK_METHOD(AsyncPacketSocket*,
+              CreateClientTcpSocket,
+              (const SocketAddress& local_address,
+               const SocketAddress&,
+               const ProxyInfo&,
+               const std::string&,
+               const PacketSocketTcpOptions&),
+              (override));
+  MOCK_METHOD(std::unique_ptr<webrtc::AsyncDnsResolverInterface>,
+              CreateAsyncDnsResolver,
+              (),
+              (override));
+};
+
+static_assert(!std::is_abstract_v<MockPacketSocketFactory>, "");
+
+}  // namespace rtc
+
+#endif  // API_TEST_MOCK_PACKET_SOCKET_FACTORY_H_