Cleanup unused methods from IceTransportInternal

Remove unused methods, add default implementations to uncalled but
overriden method selected_connection() and begin removal of the
Destroyed signal - while callers subscribe to it, nothing is calling
NotifyDestroyed().

Bug: webrtc:457682036
Change-Id: I47530ca376e4a7d0a2b06715cd50a4218a0e05bb
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/423000
Reviewed-by: Jonas Oreland <jonaso@webrtc.org>
Commit-Queue: Jonas Oreland <jonaso@webrtc.org>
Auto-Submit: Tony Herre <herre@google.com>
Cr-Commit-Position: refs/heads/main@{#46122}
diff --git a/p2p/base/ice_transport_internal.cc b/p2p/base/ice_transport_internal.cc
index c22f382..e4b6520 100644
--- a/p2p/base/ice_transport_internal.cc
+++ b/p2p/base/ice_transport_internal.cc
@@ -21,7 +21,6 @@
 #include "api/rtc_error.h"
 #include "api/units/time_delta.h"
 #include "p2p/base/p2p_constants.h"
-#include "p2p/base/transport_description.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/net_helper.h"
 
@@ -242,16 +241,6 @@
 
 IceTransportInternal::~IceTransportInternal() = default;
 
-void IceTransportInternal::SetIceCredentials(absl::string_view ice_ufrag,
-                                             absl::string_view ice_pwd) {
-  SetIceParameters(IceParameters(ice_ufrag, ice_pwd, false));
-}
-
-void IceTransportInternal::SetRemoteIceCredentials(absl::string_view ice_ufrag,
-                                                   absl::string_view ice_pwd) {
-  SetRemoteIceParameters(IceParameters(ice_ufrag, ice_pwd, false));
-}
-
 void IceTransportInternal::AddGatheringStateCallback(
     const void* removal_tag,
     absl::AnyInvocable<void(IceTransportInternal*)> callback) {
@@ -278,17 +267,4 @@
   ice_transport_state_changed_trampoline_.Subscribe(std::move(callback));
 }
 
-void IceTransportInternal::SubscribeDestroyed(
-    absl::AnyInvocable<void(IceTransportInternal*)> callback) {
-  destroyed_trampoline_.Subscribe(std::move(callback));
-}
-void IceTransportInternal::SubscribeDestroyed(
-    void* tag,
-    absl::AnyInvocable<void(IceTransportInternal*)> callback) {
-  destroyed_trampoline_.Subscribe(tag, std::move(callback));
-}
-void IceTransportInternal::UnsubscribeDestroyed(void* tag) {
-  destroyed_trampoline_.Unsubscribe(tag);
-}
-
 }  // namespace webrtc
diff --git a/p2p/base/ice_transport_internal.h b/p2p/base/ice_transport_internal.h
index cf7ceef..930f533 100644
--- a/p2p/base/ice_transport_internal.h
+++ b/p2p/base/ice_transport_internal.h
@@ -19,7 +19,6 @@
 #include <vector>
 
 #include "absl/functional/any_invocable.h"
-#include "absl/strings/string_view.h"
 #include "api/array_view.h"
 #include "api/candidate.h"
 #include "api/peer_connection_interface.h"
@@ -282,18 +281,6 @@
     RTC_CHECK_NOTREACHED();
   }
 
-  virtual void SetIceCredentials(absl::string_view ice_ufrag,
-                                 absl::string_view ice_pwd);
-
-  virtual void SetRemoteIceCredentials(absl::string_view ice_ufrag,
-                                       absl::string_view ice_pwd);
-
-  // TODO: bugs.webrtc.org/367395350 - Make virtual when all downstream
-  // overrides are gone.
-  // Returns the current local ICE parameters.
-  virtual const IceParameters* local_ice_parameters() const {
-    RTC_CHECK_NOTREACHED();
-  }
   // Returns the latest remote ICE parameters or nullptr if there are no remote
   // ICE parameters yet.
   virtual const IceParameters* remote_ice_parameters() const {
@@ -333,8 +320,9 @@
   // std::optional if there is none.
   virtual std::optional<int> GetRttEstimate() = 0;
 
+  // Default implementation in order to allow downstream override deletion.
   // TODO(qingsi): Remove this method once Chrome does not depend on it anymore.
-  virtual const Connection* selected_connection() const = 0;
+  virtual const Connection* selected_connection() const { return nullptr; }
 
   // Returns the selected candidate pair, or an empty std::optional if there is
   // none.
@@ -395,16 +383,12 @@
   void SubscribeIceTransportStateChanged(
       absl::AnyInvocable<void(IceTransportInternal*)> callback);
 
-  // Invoked when the transport is being destroyed.
-  void NotifyDestroyed(IceTransportInternal* transport) {
-    SignalDestroyed(transport);
-  }
-  void SubscribeDestroyed(
-      absl::AnyInvocable<void(IceTransportInternal*)> callback);
+  // TODO: webrtc:457682036 - Remove once downstream callers have been removed
   void SubscribeDestroyed(
       void* tag,
-      absl::AnyInvocable<void(IceTransportInternal*)> callback);
-  void UnsubscribeDestroyed(void* tag);
+      absl::AnyInvocable<void(IceTransportInternal*)> callback) {}
+  // TODO: webrtc:457682036 - Remove once downstream callers have been removed
+  void UnsubscribeDestroyed(void* tag) {}
 
   // Invoked when remote dictionary has been updated,
   // i.e. modifications to attributes from remote ice agent has
diff --git a/p2p/base/p2p_transport_channel.h b/p2p/base/p2p_transport_channel.h
index 8249c51..a89df92 100644
--- a/p2p/base/p2p_transport_channel.h
+++ b/p2p/base/p2p_transport_channel.h
@@ -64,6 +64,7 @@
 #include "rtc_base/async_packet_socket.h"
 #include "rtc_base/checks.h"
 #include "rtc_base/dscp.h"
+#include "rtc_base/net_helper.h"
 #include "rtc_base/network/received_packet.h"
 #include "rtc_base/network/sent_packet.h"
 #include "rtc_base/network_route.h"
@@ -247,11 +248,6 @@
   void SetDtlsStunPiggybackCallbacks(
       DtlsStunPiggybackCallbacks&& callbacks) override;
 
-  // Returns the local ICE parameters.
-  const IceParameters* local_ice_parameters() const override {
-    RTC_DCHECK_RUN_ON(network_thread_);
-    return &ice_parameters_;
-  }
   // Returns the latest remote ICE parameters or nullptr if there are no remote
   // ICE parameters yet.
   const IceParameters* remote_ice_parameters() const override {
diff --git a/p2p/test/fake_ice_transport.h b/p2p/test/fake_ice_transport.h
index 9288583..bf6ff9e 100644
--- a/p2p/test/fake_ice_transport.h
+++ b/p2p/test/fake_ice_transport.h
@@ -196,7 +196,7 @@
     RTC_DCHECK_RUN_ON(network_thread_);
     return remote_ice_mode_;
   }
-  const IceParameters* local_ice_parameters() const override {
+  const IceParameters* local_ice_parameters() const {
     RTC_DCHECK_RUN_ON(network_thread_);
     return &ice_parameters_;
   }
diff --git a/p2p/test/mock_ice_transport.h b/p2p/test/mock_ice_transport.h
index d76f165..93a21e9 100644
--- a/p2p/test/mock_ice_transport.h
+++ b/p2p/test/mock_ice_transport.h
@@ -59,7 +59,6 @@
   // before candidate gathering can start.
   MOCK_METHOD(void, SetIceParameters, (const IceParameters&), (override));
   MOCK_METHOD(void, SetRemoteIceParameters, (const IceParameters&), (override));
-  MOCK_METHOD(IceParameters*, local_ice_parameters, (), (const, override));
   MOCK_METHOD(IceParameters*, remote_ice_parameters, (), (const, override));
   MOCK_METHOD(void, SetRemoteIceMode, (IceMode), (override));
   MOCK_METHOD(void, SetIceConfig, (const IceConfig& config), (override));