Moves ownership of time controller into NetworkEmulationManager.

This makes it easier to maintain consistency between real time
and simulated time modes.

The RealTimeController is updated to use an explicit main thread,
this ensures that pending destruction tasks are run as the network
emulator goes out of scope.

Bug: webrtc:11255
Change-Id: Ie73ab778c78a68d7c58c0f857f14a8d8ac027c67
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/166164
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Reviewed-by: Artem Titov <titovartem@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#30342}

test/time_controller/real_time_controller.cc

@@ -14,8 +14,28 @@
 #include "system_wrappers/include/sleep.h"
 
 namespace webrtc {
+namespace {
+class MainThread : public rtc::Thread {
+ public:
+  MainThread()
+      : Thread(std::make_unique<rtc::NullSocketServer>(), false),
+        current_setter_(this) {
+    DoInit();
+  }
+  ~MainThread() {
+    Stop();
+    DoDestroy();
+  }
+
+ private:
+  CurrentThreadSetter current_setter_;
+};
+}  // namespace
 RealTimeController::RealTimeController()
-    : task_queue_factory_(CreateDefaultTaskQueueFactory()) {}
+    : task_queue_factory_(CreateDefaultTaskQueueFactory()),
+      main_thread_(std::make_unique<MainThread>()) {
+  main_thread_->SetName("Main", this);
+}
 
 Clock* RealTimeController::GetClock() {
   return Clock::GetRealTimeClock();
@@ -42,16 +62,11 @@ std::unique_ptr<rtc::Thread> RealTimeController::CreateThread(
 }
 
 rtc::Thread* RealTimeController::GetMainThread() {
-  return rtc::Thread::Current();
+  return main_thread_.get();
 }
 
 void RealTimeController::AdvanceTime(TimeDelta duration) {
-  GetMainThread()->ProcessMessages(duration.ms());
-}
-
-RealTimeController* GlobalRealTimeController() {
-  static RealTimeController* time_controller = new RealTimeController();
-  return time_controller;
+  main_thread_->ProcessMessages(duration.ms());
 }
 
 }  // namespace webrtc

test/time_controller/real_time_controller.h

@@ -36,10 +36,9 @@ class RealTimeController : public TimeController {
 
  private:
   const std::unique_ptr<TaskQueueFactory> task_queue_factory_;
+  const std::unique_ptr<rtc::Thread> main_thread_;
 };
 
-RealTimeController* GlobalRealTimeController();
-
 }  // namespace webrtc
 
 #endif  // TEST_TIME_CONTROLLER_REAL_TIME_CONTROLLER_H_

test/time_controller/simulated_thread.h

@@ -19,20 +19,7 @@ namespace webrtc {
 class SimulatedThread : public rtc::Thread,
                         public sim_time_impl::SimulatedSequenceRunner {
  public:
-  class CurrentThreadSetter : CurrentTaskQueueSetter {
-   public:
-    explicit CurrentThreadSetter(Thread* thread)
-        : CurrentTaskQueueSetter(thread),
-          manager_(rtc::ThreadManager::Instance()),
-          previous_(manager_->CurrentThread()) {
-      manager_->ChangeCurrentThreadForTest(thread);
-    }
-    ~CurrentThreadSetter() { manager_->ChangeCurrentThreadForTest(previous_); }
-
-   private:
-    rtc::ThreadManager* const manager_;
-    rtc::Thread* const previous_;
-  };
+  using CurrentThreadSetter = CurrentThreadSetter;
   SimulatedThread(sim_time_impl::SimulatedTimeControllerImpl* handler,
                   absl::string_view name,
                   std::unique_ptr<rtc::SocketServer> socket_server);