Update IWYU tool with a mapping file

Also apply IWYU to all .cc files in pc/, and correct BUILD file to match.
Note: Some files came out wrong when iwyu was applied. These are not included.

Bug: none
Change-Id: Ib5ea46b8fcc505414d0447cca7218ad3afc2e321
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/252280
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Commit-Queue: Harald Alvestrand <hta@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36064}
diff --git a/pc/rtp_sender_receiver_unittest.cc b/pc/rtp_sender_receiver_unittest.cc
index d947b8b..c0b09e3 100644
--- a/pc/rtp_sender_receiver_unittest.cc
+++ b/pc/rtp_sender_receiver_unittest.cc
@@ -11,6 +11,7 @@
 #include <stddef.h>
 
 #include <cstdint>
+#include <iterator>
 #include <memory>
 #include <string>
 #include <utility>
@@ -28,15 +29,20 @@
 #include "api/rtc_error.h"
 #include "api/rtc_event_log/rtc_event_log.h"
 #include "api/rtp_parameters.h"
+#include "api/rtp_receiver_interface.h"
 #include "api/scoped_refptr.h"
 #include "api/test/fake_frame_decryptor.h"
 #include "api/test/fake_frame_encryptor.h"
 #include "api/video/builtin_video_bitrate_allocator_factory.h"
+#include "api/video/video_bitrate_allocator_factory.h"
+#include "api/video/video_codec_constants.h"
 #include "media/base/codec.h"
+#include "media/base/delayable.h"
 #include "media/base/fake_media_engine.h"
 #include "media/base/media_channel.h"
 #include "media/base/media_config.h"
 #include "media/base/media_engine.h"
+#include "media/base/rid_description.h"
 #include "media/base/stream_params.h"
 #include "media/base/test_utils.h"
 #include "media/engine/fake_webrtc_call.h"
@@ -50,8 +56,6 @@
 #include "pc/dtls_srtp_transport.h"
 #include "pc/local_audio_source.h"
 #include "pc/media_stream.h"
-#include "pc/remote_audio_source.h"
-#include "pc/rtp_receiver.h"
 #include "pc/rtp_sender.h"
 #include "pc/rtp_transport_internal.h"
 #include "pc/test/fake_video_track_source.h"
@@ -59,6 +63,8 @@
 #include "pc/video_track.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/gunit.h"
+#include "rtc_base/location.h"
+#include "rtc_base/ref_counted_object.h"
 #include "rtc_base/third_party/sigslot/sigslot.h"
 #include "rtc_base/thread.h"
 #include "test/gmock.h"