diff --git a/pc/BUILD.gn b/pc/BUILD.gn
index 40006424fa..b79cd3c788 100644
--- a/pc/BUILD.gn
+++ b/pc/BUILD.gn
@@ -939,7 +939,6 @@ rtc_source_set("data_channel_controller") {
     "data_channel_controller.h",
   ]
   deps = [
-    ":channel",
     ":data_channel_utils",
     ":peer_connection_internal",
     ":sctp_data_channel",
@@ -950,15 +949,15 @@ rtc_source_set("data_channel_controller") {
     "../api:sequence_checker",
     "../api/transport:datagram_transport_interface",
     "../media:rtc_media_base",
+    "../rtc_base",
     "../rtc_base:checks",
     "../rtc_base:logging",
     "../rtc_base:macromagic",
-    "../rtc_base:rtc_base",
     "../rtc_base:rtc_base_approved",
     "../rtc_base:threading",
     "../rtc_base:weak_ptr",
     "../rtc_base/task_utils:to_queued_task",
-    "../rtc_base/third_party/sigslot:sigslot",
+    "../rtc_base/third_party/sigslot",
   ]
   absl_deps = [
     "//third_party/abseil-cpp/absl/algorithm:container",
@@ -1064,9 +1063,7 @@ rtc_source_set("sdp_offer_answer") {
     ":channel_manager",
     ":connection_context",
     ":data_channel_controller",
-    ":data_channel_utils",
     ":dtls_transport",
-    ":ice_server_parsing",
     ":jsep_transport_controller",
     ":media_session",
     ":media_stream",
@@ -1074,7 +1071,6 @@ rtc_source_set("sdp_offer_answer") {
     ":media_stream_proxy",
     ":peer_connection_internal",
     ":peer_connection_message_handler",
-    ":rtc_stats_collector",
     ":rtp_media_utils",
     ":rtp_receiver",
     ":rtp_receiver_proxy",
@@ -1082,7 +1078,6 @@ rtc_source_set("sdp_offer_answer") {
     ":rtp_sender_proxy",
     ":rtp_transceiver",
     ":rtp_transmission_manager",
-    ":sctp_transport",
     ":sdp_state_provider",
     ":session_description",
     ":simulcast_description",
@@ -1101,24 +1096,21 @@ rtc_source_set("sdp_offer_answer") {
     "../api:scoped_refptr",
     "../api:sequence_checker",
     "../api/crypto:options",
-    "../api/transport:datagram_transport_interface",
     "../api/video:builtin_video_bitrate_allocator_factory",
     "../api/video:video_bitrate_allocator_factory",
     "../media:rtc_media_base",
     "../p2p:rtc_p2p",
+    "../rtc_base",
     "../rtc_base:checks",
     "../rtc_base:logging",
     "../rtc_base:macromagic",
     "../rtc_base:refcount",
-    "../rtc_base:rtc_base",
     "../rtc_base:rtc_base_approved",
     "../rtc_base:rtc_operations_chain",
     "../rtc_base:stringutils",
     "../rtc_base:threading",
     "../rtc_base:weak_ptr",
-    "../rtc_base/experiments:field_trial_parser",
-    "../rtc_base/third_party/sigslot:sigslot",
-    "../system_wrappers:field_trial",
+    "../rtc_base/third_party/sigslot",
     "../system_wrappers:metrics",
   ]
   absl_deps = [
@@ -1179,18 +1171,15 @@ rtc_source_set("peer_connection") {
     ":session_description",
     ":simulcast_description",
     ":stats_collector",
-    ":stream_collection",
     ":transceiver_list",
     ":transport_stats",
     ":usage_pattern",
     ":webrtc_session_description_factory",
     "../api:async_dns_resolver",
     "../api:field_trials_view",
-    "../api:field_trials_view",
     "../api:libjingle_logging_api",
     "../api:libjingle_peerconnection_api",
     "../api:media_stream_interface",
-    "../api:packet_socket_factory",
     "../api:rtc_error",
     "../api:rtc_stats_api",
     "../api:rtp_parameters",
@@ -1199,33 +1188,31 @@ rtc_source_set("peer_connection") {
     "../api:sequence_checker",
     "../api/adaptation:resource_adaptation_api",
     "../api/crypto:options",
-    "../api/rtc_event_log:rtc_event_log",
+    "../api/rtc_event_log",
     "../api/transport:bitrate_settings",
     "../api/transport:datagram_transport_interface",
     "../api/transport:enums",
-    "../api/video:video_bitrate_allocator_factory",
     "../api/video:video_codec_constants",
     "../call:call_interfaces",
     "../media:rtc_media_base",
     "../media:rtc_media_config",
     "../modules/rtp_rtcp:rtp_rtcp_format",
     "../p2p:rtc_p2p",
+    "../rtc_base",
     "../rtc_base:checks",
     "../rtc_base:ip_address",
     "../rtc_base:logging",
     "../rtc_base:macromagic",
     "../rtc_base:network_constants",
     "../rtc_base:refcount",
-    "../rtc_base:rtc_base",
     "../rtc_base:rtc_base_approved",
     "../rtc_base:socket_address",
     "../rtc_base:stringutils",
     "../rtc_base:threading",
     "../rtc_base:weak_ptr",
-    "../rtc_base/network:sent_packet",
     "../rtc_base/task_utils:pending_task_safety_flag",
     "../rtc_base/task_utils:to_queued_task",
-    "../rtc_base/third_party/sigslot:sigslot",
+    "../rtc_base/third_party/sigslot",
     "../system_wrappers:metrics",
   ]
   absl_deps = [
@@ -2253,11 +2240,8 @@ if (rtc_include_tests && !build_with_chromium) {
       ":media_stream",
       ":peer_connection",
       ":peer_connection_factory",
-      ":peer_connection_factory",
       ":peer_connection_proxy",
-      ":peerconnection",
       ":proxy",
-      ":remote_audio_source",
       ":rtc_stats_collector",
       ":rtc_stats_traversal",
       ":rtp_media_utils",
@@ -2290,12 +2274,10 @@ if (rtc_include_tests && !build_with_chromium) {
       "../api:fake_frame_decryptor",
       "../api:fake_frame_encryptor",
       "../api:field_trials_view",
-      "../api:field_trials_view",
       "../api:function_view",
       "../api:libjingle_logging_api",
       "../api:libjingle_peerconnection_api",
       "../api:media_stream_interface",
-      "../api:mock_rtp",
       "../api:mock_video_track",
       "../api:packet_socket_factory",
       "../api:priority",
@@ -2332,9 +2314,7 @@ if (rtc_include_tests && !build_with_chromium) {
       "../media:rtc_media_engine_defaults",
       "../modules/audio_device:audio_device_api",
       "../modules/audio_processing:audio_processing_statistics",
-      "../modules/audio_processing:audioproc_test_utils",
       "../modules/rtp_rtcp:rtp_rtcp_format",
-      "../p2p:fake_ice_transport",
       "../p2p:fake_port_allocator",
       "../p2p:p2p_server_utils",
       "../rtc_base:checks",
@@ -2346,20 +2326,14 @@ if (rtc_include_tests && !build_with_chromium) {
       "../rtc_base:rtc_base_tests_utils",
       "../rtc_base:rtc_json",
       "../rtc_base:socket_address",
-      "../rtc_base:socket_factory",
       "../rtc_base:threading",
       "../rtc_base/synchronization:mutex",
       "../rtc_base/third_party/base64",
       "../rtc_base/third_party/sigslot",
-      "../system_wrappers:field_trial",
       "../system_wrappers:metrics",
-      "../test:explicit_key_value_config",
-      "../test:fileutils",
-      "../test:rtp_test_utils",
       "../test:scoped_key_value_config",
       "../test:test_common",
       "../test/pc/sctp:fake_sctp_transport",
-      "./scenario_tests:pc_scenario_tests",
       "//third_party/abseil-cpp/absl/algorithm:container",
       "//third_party/abseil-cpp/absl/memory",
       "//third_party/abseil-cpp/absl/strings",
diff --git a/pc/data_channel_controller.h b/pc/data_channel_controller.h
index fa10b745c6..a3efe41ad0 100644
--- a/pc/data_channel_controller.h
+++ b/pc/data_channel_controller.h
@@ -11,10 +11,6 @@
 #ifndef PC_DATA_CHANNEL_CONTROLLER_H_
 #define PC_DATA_CHANNEL_CONTROLLER_H_
 
-#include <stdint.h>
-
-#include <map>
-#include <memory>
 #include <string>
 #include <vector>
 
@@ -24,9 +20,6 @@
 #include "api/sequence_checker.h"
 #include "api/transport/data_channel_transport_interface.h"
 #include "media/base/media_channel.h"
-#include "media/base/media_engine.h"
-#include "media/base/stream_params.h"
-#include "pc/channel.h"
 #include "pc/data_channel_utils.h"
 #include "pc/sctp_data_channel.h"
 #include "rtc_base/checks.h"
diff --git a/pc/sdp_offer_answer.cc b/pc/sdp_offer_answer.cc
index a9501caa5e..c592c3556c 100644
--- a/pc/sdp_offer_answer.cc
+++ b/pc/sdp_offer_answer.cc
@@ -17,7 +17,6 @@
 #include <memory>
 #include <queue>
 #include <string>
-#include <type_traits>
 #include <utility>
 
 #include "absl/algorithm/container.h"
diff --git a/pc/sdp_offer_answer.h b/pc/sdp_offer_answer.h
index 15c092723e..532d8cc596 100644
--- a/pc/sdp_offer_answer.h
+++ b/pc/sdp_offer_answer.h
@@ -19,7 +19,6 @@
 #include <memory>
 #include <set>
 #include <string>
-#include <utility>
 #include <vector>
 
 #include "absl/types/optional.h"
@@ -37,40 +36,29 @@
 #include "api/sequence_checker.h"
 #include "api/set_local_description_observer_interface.h"
 #include "api/set_remote_description_observer_interface.h"
-#include "api/transport/data_channel_transport_interface.h"
-#include "api/turn_customizer.h"
 #include "api/uma_metrics.h"
 #include "api/video/video_bitrate_allocator_factory.h"
 #include "media/base/media_channel.h"
 #include "media/base/stream_params.h"
 #include "p2p/base/port_allocator.h"
 #include "pc/channel.h"
-#include "pc/channel_interface.h"
 #include "pc/channel_manager.h"
 #include "pc/connection_context.h"
 #include "pc/data_channel_controller.h"
-#include "pc/ice_server_parsing.h"
 #include "pc/jsep_transport_controller.h"
 #include "pc/media_session.h"
 #include "pc/media_stream_observer.h"
 #include "pc/peer_connection_internal.h"
-#include "pc/rtc_stats_collector.h"
 #include "pc/rtp_receiver.h"
-#include "pc/rtp_sender.h"
 #include "pc/rtp_transceiver.h"
 #include "pc/rtp_transmission_manager.h"
-#include "pc/sctp_transport.h"
 #include "pc/sdp_state_provider.h"
 #include "pc/session_description.h"
-#include "pc/stats_collector.h"
 #include "pc/stream_collection.h"
 #include "pc/transceiver_list.h"
 #include "pc/webrtc_session_description_factory.h"
 #include "rtc_base/checks.h"
-#include "rtc_base/experiments/field_trial_parser.h"
 #include "rtc_base/operations_chain.h"
-#include "rtc_base/race_checker.h"
-#include "rtc_base/rtc_certificate.h"
 #include "rtc_base/ssl_stream_adapter.h"
 #include "rtc_base/third_party/sigslot/sigslot.h"
 #include "rtc_base/thread.h"