TaskManager refactor: avoid using Simulator::Schedule()

diff --git a/model/dce.cc b/model/dce.cc
--- a/model/dce.cc
+++ b/model/dce.cc
@@ -502,8 +502,9 @@
 {
   if (!process->itimerInterval.IsZero ())
     {
-      process->itimer = Simulator::Schedule (process->itimerInterval,
-                                             &Itimer, process);
+      process->itimer = Simulator::ScheduleWithContext (Simulator::GetContext (),
+                                                        process->itimerInterval,
+                                                        &Itimer, process);
     }
   // wakeup one thread
   UtilsSendSignal (process, SIGALRM);
@@ -551,8 +552,9 @@
     {
       return 0;
     }
-  current->process->itimer = Simulator::Schedule (UtilsTimevalToTime (value->it_value),
-                                                  &Itimer, current->process);
+  current->process->itimer = Simulator::ScheduleWithContext (Simulator::GetContext (),
+                                                             UtilsTimevalToTime (value->it_value),
+                                                             &Itimer, current->process);
   return 0;
 }
 char * dce_getcwd (char *buf, size_t size)
diff --git a/model/linux-socket-fd-factory.cc b/model/linux-socket-fd-factory.cc
--- a/model/linux-socket-fd-factory.cc
+++ b/model/linux-socket-fd-factory.cc
@@ -198,9 +198,9 @@
 {
   LinuxSocketFdFactory *self = (LinuxSocketFdFactory *)kernel;
   Ptr<EventIdHolder> ev = Create<EventIdHolder> ();
-  EventId event = Simulator::Schedule (NanoSeconds (ns),
-                                       &LinuxSocketFdFactory::EventTrampoline,
-                                       self, fn, context, pre_fn, ev);
+  EventId event = Simulator::ScheduleWithContext (Simulator::GetContext (), NanoSeconds (ns),
+                                                  &LinuxSocketFdFactory::EventTrampoline,
+                                                  self, fn, context, pre_fn, ev);
   ev->id = event;
   return &ev->id;
 }
diff --git a/model/task-manager.cc b/model/task-manager.cc
--- a/model/task-manager.cc
+++ b/model/task-manager.cc
@@ -9,6 +9,7 @@
 #include "ns3/simulator.h"
 #include "ns3/node.h"
 #include "ns3/node-list.h"
+#include "ns3/event-id.h"
 #include "dce-manager.h"
 #include "dce-stdio.h"
 #include "process.h"
@@ -295,7 +296,8 @@
   m_scheduler->Enqueue (task);
   if (!m_nextSchedule.IsRunning ())
     {
-      m_nextSchedule = Simulator::ScheduleNow (&TaskManager::Schedule, this);
+      m_nextSchedule = Simulator::ScheduleWithContext (Simulator::GetContext (), Seconds (0.0),
+                                                       &TaskManager::Schedule, this);
     }
 }
 
@@ -321,7 +323,9 @@
   current->m_state = Task::BLOCKED;
   if (!timeout.IsZero ())
     {
-      current->m_waitTimer = Simulator::Schedule (timeout, &TaskManager::EndWait, this, current);
+      current->m_waitTimer = Simulator::ScheduleWithContext (Simulator::GetContext (), timeout,
+                                                             &TaskManager::EndWait, this, current);
+
     }
   Schedule ();
   current->m_waitTimer.Cancel ();
@@ -355,7 +359,8 @@
   m_deadTasks.push_back (current);
   if (!m_nextGc.IsRunning ())
     {
-      m_nextGc = Simulator::ScheduleNow (&TaskManager::GarbageCollectDeadTasks, this);
+      m_nextGc = Simulator::ScheduleWithContext (Simulator::GetContext (), Simulator::Now (),
+                                                 &TaskManager::GarbageCollectDeadTasks, this);
     }
   Schedule ();
 }
@@ -417,7 +422,9 @@
         {
           // but before leaving, we check if we have further processes active, and,
           // if so, make sure we will schedule them later.
-          Simulator::Schedule (delay, &TaskManager::Schedule, this);
+          Thread* thread = (Thread *)next->GetContext ();
+          Simulator::ScheduleWithContext (Simulator::GetContext (), delay,
+                                          &TaskManager::Schedule, this);
         }
       struct Fiber *fiber = m_current->m_fiber;
       if (m_current->m_switchNotifier != 0)
diff --git a/model/unix-timer-fd.cc b/model/unix-timer-fd.cc
--- a/model/unix-timer-fd.cc
+++ b/model/unix-timer-fd.cc
@@ -207,9 +207,10 @@
 {
   if (!m_period.IsZero ())
     {
-      m_timer = Simulator::Schedule (m_period,
-                                     &UnixTimerFd::TimerExpired,
-                                     this);
+      m_timer = Simulator::ScheduleWithContext (Simulator::GetContext (), 
+                                                m_period,
+                                                &UnixTimerFd::TimerExpired,
+                                                this);
     }
   m_skipped++;
   if (m_waiter != 0)
@@ -233,9 +234,10 @@
   Time initial = UtilsTimespecToTime (new_value->it_value);
   if (!initial.IsZero ())
     {
-      m_timer = Simulator::Schedule (initial,
-                                     &UnixTimerFd::TimerExpired,
-                                     this);
+      m_timer = Simulator::ScheduleWithContext (Simulator::GetContext (),
+                                                initial,
+                                                &UnixTimerFd::TimerExpired,
+                                                this);
     }
   return 0;
 }