Replace rtc::Optional with absl::optional in test and rtc_tools

This is a no-op change because rtc::Optional is an alias to absl::optional

This CL generated by running script with parameters 'test rtc_tools'

find $@ -type f \( -name \*.h -o -name \*.cc \) \
-exec sed -i 's|rtc::Optional|absl::optional|g' {} \+ \
-exec sed -i 's|rtc::nullopt|absl::nullopt|g' {} \+ \
-exec sed -i 's|#include "api/optional.h"|#include "absl/types/optional.h"|' {} \+

find $@ -type f -name BUILD.gn \
-exec sed -r -i 's|"(../)*api:optional"|"//third_party/abseil-cpp/absl/types:optional"|' {} \+;

git cl format

Bug: webrtc:9078
Change-Id: Ibb43c737f4c45fe300736382b0dd2d8ab32c6377
Reviewed-on: https://webrtc-review.googlesource.com/83944
Reviewed-by: Patrik Höglund <phoglund@webrtc.org>
Commit-Queue: Danil Chapovalov <danilchap@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23642}
diff --git a/rtc_tools/network_tester/test_controller.cc b/rtc_tools/network_tester/test_controller.cc
index a3a8833..e5bd92e 100644
--- a/rtc_tools/network_tester/test_controller.cc
+++ b/rtc_tools/network_tester/test_controller.cc
@@ -37,7 +37,7 @@
   udp_transport_->SetRemoteAddress(rtc::SocketAddress(hostname, port));
   NetworkTesterPacket packet;
   packet.set_type(NetworkTesterPacket::HAND_SHAKING);
-  SendData(packet, rtc::nullopt);
+  SendData(packet, absl::nullopt);
   rtc::CritScope scoped_lock(&local_test_done_lock_);
   local_test_done_ = false;
   remote_test_done_ = false;
@@ -49,7 +49,7 @@
 }
 
 void TestController::SendData(const NetworkTesterPacket& packet,
-                              rtc::Optional<size_t> data_size) {
+                              absl::optional<size_t> data_size) {
   // Can be call from packet_sender or from test_controller thread.
   size_t packet_size = packet.ByteSizeLong();
   send_data_[0] = packet_size;
@@ -65,7 +65,7 @@
   RTC_DCHECK_CALLED_SEQUENTIALLY(&packet_sender_checker_);
   NetworkTesterPacket packet;
   packet.set_type(NetworkTesterPacket::TEST_DONE);
-  SendData(packet, rtc::nullopt);
+  SendData(packet, absl::nullopt);
   rtc::CritScope scoped_lock(&local_test_done_lock_);
   local_test_done_ = true;
 }
@@ -92,7 +92,7 @@
       NetworkTesterPacket packet;
       packet.set_type(NetworkTesterPacket::TEST_START);
       udp_transport_->SetRemoteAddress(remote_addr);
-      SendData(packet, rtc::nullopt);
+      SendData(packet, absl::nullopt);
       packet_sender_.reset(new PacketSender(this, config_file_path_));
       packet_sender_->StartSending();
       rtc::CritScope scoped_lock(&local_test_done_lock_);