Reland the CL to remove candidates when doing continual gathering

webrtc/p2p/base/transportcontroller.cc

Index: webrtc/p2p/base/transportcontroller.cc
diff --git a/webrtc/p2p/base/transportcontroller.cc b/webrtc/p2p/base/transportcontroller.cc
index 053388eeb8130d30fec9a6fb5a21e94ec54a8b0a..128d2fc656406d75b7b094baf1e8a57cd32513e1 100644
--- a/webrtc/p2p/base/transportcontroller.cc
+++ b/webrtc/p2p/base/transportcontroller.cc
@@ -127,6 +127,12 @@ bool TransportController::AddRemoteCandidates(const std::string& transport_name,
                 transport_name, candidates, err));
 }
 
+bool TransportController::RemoveRemoteCandidates(const Candidates& candidates,
+                                                 std::string* err) {
+  return worker_thread_->Invoke<bool>(rtc::Bind(
+      &TransportController::RemoveRemoteCandidates_w, this, candidates, err));
+}
+
 bool TransportController::ReadyForRemoteCandidates(
     const std::string& transport_name) {
   return worker_thread_->Invoke<bool>(rtc::Bind(
@@ -162,6 +168,8 @@ TransportChannel* TransportController::CreateTransportChannel_w(
       this, &TransportController::OnChannelGatheringState_w);
   channel->SignalCandidateGathered.connect(
       this, &TransportController::OnChannelCandidateGathered_w);
+  channel->SignalCandidatesRemoved.connect(
+      this, &TransportController::OnChannelCandidatesRemoved_w);
   channel->SignalRoleConflict.connect(
       this, &TransportController::OnChannelRoleConflict_w);
   channel->SignalConnectionRemoved.connect(
@@ -460,6 +468,28 @@ bool TransportController::AddRemoteCandidates_w(
   return transport->AddRemoteCandidates(candidates, err);
 }
 
+bool TransportController::RemoveRemoteCandidates_w(const Candidates& candidates,
+                                                   std::string* err) {
+  RTC_DCHECK(worker_thread()->IsCurrent());
+  std::map<std::string, Candidates> candidates_by_transport_name;
+  for (const Candidate& cand : candidates) {
+    RTC_DCHECK(!cand.transport_name().empty());
+    candidates_by_transport_name[cand.transport_name()].push_back(cand);
+  }
+
+  bool result = true;
+  for (auto kv : candidates_by_transport_name) {
+    Transport* transport = GetTransport_w(kv.first);
+    if (!transport) {
+      // If we didn't find a transport, that's not an error;
+      // it could have been deleted as a result of bundling.
+      continue;
+    }
+    result &= transport->RemoveRemoteCandidates(kv.second, err);
+  }
+  return result;
+}
+
 bool TransportController::ReadyForRemoteCandidates_w(
     const std::string& transport_name) {
   RTC_DCHECK(worker_thread()->IsCurrent());
@@ -518,6 +548,21 @@ void TransportController::OnChannelCandidateGathered_w(
   signaling_thread_->Post(this, MSG_CANDIDATESGATHERED, data);
 }
 
+void TransportController::OnChannelCandidatesRemoved_w(
+    TransportChannelImpl* channel,
+    const Candidates& candidates) {
+  invoker_.AsyncInvoke<void>(
+      signaling_thread_,
+      rtc::Bind(&TransportController::OnChannelCandidatesRemoved, this,
+                candidates));
+}
+
+void TransportController::OnChannelCandidatesRemoved(
+    const Candidates& candidates) {
+  RTC_DCHECK(signaling_thread_->IsCurrent());
+  SignalCandidatesRemoved(candidates);
+}
+
 void TransportController::OnChannelRoleConflict_w(
     TransportChannelImpl* channel) {
   RTC_DCHECK(worker_thread_->IsCurrent());