Delete webrtc::PacketTime and backwards compatibility.

This is a followup to
https://webrtc-review.googlesource.com/c/src/+/91840, which needed
transitional methods while updating downstream code. This cl completes
the deletion, and can be landed after downstream code is updated.

Bug: webtrc:9584
Change-Id: I4d3654748973a4757a8d79bb93f524c630a0eca3
Reviewed-on: https://webrtc-review.googlesource.com/93285
Commit-Queue: Oleh Prypin <oprypin@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24329}
diff --git a/call/BUILD.gn b/call/BUILD.gn
index d09ae35..7965097 100644
--- a/call/BUILD.gn
+++ b/call/BUILD.gn
@@ -20,7 +20,6 @@
     "call_config.h",
     "flexfec_receive_stream.cc",
     "flexfec_receive_stream.h",
-    "packet_receiver.cc",
     "packet_receiver.h",
     "syncable.cc",
     "syncable.h",
diff --git a/call/fake_network_pipe.cc b/call/fake_network_pipe.cc
index 55af767..a71ba4d 100644
--- a/call/fake_network_pipe.cc
+++ b/call/fake_network_pipe.cc
@@ -44,23 +44,6 @@
       media_type_(media_type),
       packet_time_us_(packet_time_us) {}
 
-NetworkPacket::NetworkPacket(rtc::CopyOnWriteBuffer packet,
-                             int64_t send_time,
-                             int64_t arrival_time,
-                             absl::optional<PacketOptions> packet_options,
-                             bool is_rtcp,
-                             MediaType media_type,
-                             absl::optional<PacketTime> packet_time)
-    : NetworkPacket(packet,
-                    send_time,
-                    arrival_time,
-                    packet_options,
-                    is_rtcp,
-                    media_type,
-                    packet_time
-                        ? absl::optional<int64_t>(packet_time->timestamp)
-                        : absl::nullopt) {}
-
 NetworkPacket::NetworkPacket(NetworkPacket&& o)
     : packet_(std::move(o.packet_)),
       send_time_(o.send_time_),
@@ -215,25 +198,11 @@
                                     bool is_rtcp,
                                     MediaType media_type,
                                     absl::optional<int64_t> packet_time_us) {
-  absl::optional<PacketTime> packet_time;
-  if (packet_time_us) {
-    packet_time = PacketTime(*packet_time_us, -1);
-  }
-  return EnqueuePacket(packet, options, is_rtcp, media_type, packet_time);
-}
-
-bool FakeNetworkPipe::EnqueuePacket(rtc::CopyOnWriteBuffer packet,
-                                    absl::optional<PacketOptions> options,
-                                    bool is_rtcp,
-                                    MediaType media_type,
-                                    absl::optional<PacketTime> packet_time) {
   int64_t time_now_us = clock_->TimeInMicroseconds();
   rtc::CritScope crit(&process_lock_);
   size_t packet_size = packet.size();
-  NetworkPacket net_packet(
-      std::move(packet), time_now_us, time_now_us, options, is_rtcp, media_type,
-      packet_time ? absl::optional<int64_t>(packet_time->timestamp)
-                  : absl::nullopt);
+  NetworkPacket net_packet(std::move(packet), time_now_us, time_now_us, options,
+                           is_rtcp, media_type, packet_time_us);
 
   packets_in_flight_.emplace_back(StoredPacket(std::move(net_packet)));
   int64_t packet_id = reinterpret_cast<uint64_t>(&packets_in_flight_.back());
diff --git a/call/fake_network_pipe.h b/call/fake_network_pipe.h
index 1f660b8..a46cd75 100644
--- a/call/fake_network_pipe.h
+++ b/call/fake_network_pipe.h
@@ -43,14 +43,6 @@
                 bool is_rtcp,
                 MediaType media_type,
                 absl::optional<int64_t> packet_time_us);
-  // TODO(nisse): Deprecated.
-  NetworkPacket(rtc::CopyOnWriteBuffer packet,
-                int64_t send_time,
-                int64_t arrival_time,
-                absl::optional<PacketOptions> packet_options,
-                bool is_rtcp,
-                MediaType media_type,
-                absl::optional<PacketTime> packet_time);
 
   // Disallow copy constructor and copy assignment (no deep copies of |data_|).
   NetworkPacket(const NetworkPacket&) = delete;
@@ -74,10 +66,6 @@
   bool is_rtcp() const { return is_rtcp_; }
   MediaType media_type() const { return media_type_; }
   absl::optional<int64_t> packet_time_us() const { return packet_time_us_; }
-  // TODO(nisse): Deprecated.
-  PacketTime packet_time() const {
-    return PacketTime(packet_time_us_.value_or(-1), -1);
-  }
 
  private:
   rtc::CopyOnWriteBuffer packet_;
@@ -218,19 +206,11 @@
                              MediaType media_type,
                              absl::optional<int64_t> packet_time_us);
 
-  // TODO(nisse): Deprecated. Delete as soon as overrides in downstream code are
-  // updated.
-  virtual bool EnqueuePacket(rtc::CopyOnWriteBuffer packet,
-                             absl::optional<PacketOptions> options,
-                             bool is_rtcp,
-                             MediaType media_type,
-                             absl::optional<PacketTime> packet_time);
   bool EnqueuePacket(rtc::CopyOnWriteBuffer packet,
                      absl::optional<PacketOptions> options,
                      bool is_rtcp,
                      MediaType media_type) {
-    return EnqueuePacket(packet, options, is_rtcp, media_type,
-                         absl::optional<PacketTime>());
+    return EnqueuePacket(packet, options, is_rtcp, media_type, absl::nullopt);
   }
   void DeliverNetworkPacket(NetworkPacket* packet)
       RTC_EXCLUSIVE_LOCKS_REQUIRED(config_lock_);
diff --git a/call/packet_receiver.cc b/call/packet_receiver.cc
deleted file mode 100644
index d6786d2..0000000
--- a/call/packet_receiver.cc
+++ /dev/null
@@ -1,31 +0,0 @@
-/*
- *  Copyright (c) 2018 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.
- */
-
-#include "call/packet_receiver.h"
-
-namespace webrtc {
-
-PacketReceiver::DeliveryStatus PacketReceiver::DeliverPacket(
-    MediaType media_type,
-    rtc::CopyOnWriteBuffer packet,
-    int64_t packet_time_us) {
-  return DeliverPacket(media_type, packet, PacketTime(packet_time_us, -1));
-}
-
-// TODO(bugs.webrtc.org/9584): Deprecated. Over the transition, default
-// implementations are used, and subclasses must override one or the other.
-PacketReceiver::DeliveryStatus PacketReceiver::DeliverPacket(
-    MediaType media_type,
-    rtc::CopyOnWriteBuffer packet,
-    const PacketTime& packet_time) {
-  return DeliverPacket(media_type, packet, packet_time.timestamp);
-}
-
-}  // namespace webrtc
diff --git a/call/packet_receiver.h b/call/packet_receiver.h
index 2a0e3ef..f05e409 100644
--- a/call/packet_receiver.h
+++ b/call/packet_receiver.h
@@ -31,13 +31,7 @@
 
   virtual DeliveryStatus DeliverPacket(MediaType media_type,
                                        rtc::CopyOnWriteBuffer packet,
-                                       int64_t packet_time_us);
-
-  // TODO(bugs.webrtc.org/9584): Deprecated. Over the transition, default
-  // implementations are used, and subclasses must override one or the other.
-  virtual DeliveryStatus DeliverPacket(MediaType media_type,
-                                       rtc::CopyOnWriteBuffer packet,
-                                       const PacketTime& packet_time);
+                                       int64_t packet_time_us) = 0;
 
  protected:
   virtual ~PacketReceiver() {}
diff --git a/common_types.h b/common_types.h
index c9eeee4..c1c5b4e 100644
--- a/common_types.h
+++ b/common_types.h
@@ -404,24 +404,6 @@
   double initial_var_noise;
 };
 
-// TODO(nisse): This struct is phased out, delete as soon as down stream code is
-// updated.
-
-// This structure will have the information about when packet is actually
-// received by socket.
-struct PacketTime {
-  PacketTime() : timestamp(-1), not_before(-1) {}
-  PacketTime(int64_t timestamp, int64_t not_before)
-      : timestamp(timestamp), not_before(not_before) {}
-
-  int64_t timestamp;   // Receive time after socket delivers the data.
-  int64_t not_before;  // Earliest possible time the data could have arrived,
-                       // indicating the potential error in the |timestamp|
-                       // value,in case the system is busy.
-                       // For example, the time of the last select() call.
-                       // If unknown, this value will be set to zero.
-};
-
 // Minimum and maximum playout delay values from capture to render.
 // These are best effort values.
 //