Mark handlers in AOS as noexcept

AOS isn't exception safe.  Ajay just spent a lot of time debugging
exception safety.  Let's mark the callbacks in AOS as not exception safe
to catch this at the source.

Change-Id: Icdd7de207837f9379440c32a07cc40e119321353
Signed-off-by: Austin Schuh <austin.schuh@bluerivertech.com>
diff --git a/aos/events/event_loop_event.h b/aos/events/event_loop_event.h
index 808a4fe..a86f670 100644
--- a/aos/events/event_loop_event.h
+++ b/aos/events/event_loop_event.h
@@ -32,7 +32,7 @@
   }
   void set_generation(size_t generation) { generation_ = generation; }
 
-  virtual void HandleEvent() = 0;
+  virtual void HandleEvent() noexcept = 0;
 
  private:
   monotonic_clock::time_point event_time_ = monotonic_clock::max_time;
@@ -45,7 +45,7 @@
  public:
   EventHandler(T *t) : t_(t) {}
   ~EventHandler() override = default;
-  void HandleEvent() override { t_->HandleEvent(); }
+  void HandleEvent() noexcept override { t_->HandleEvent(); }
 
  private:
   T *const t_;
diff --git a/aos/events/simulated_event_loop.cc b/aos/events/simulated_event_loop.cc
index 083e246..736bd6e 100644
--- a/aos/events/simulated_event_loop.cc
+++ b/aos/events/simulated_event_loop.cc
@@ -127,7 +127,7 @@
 
   void Schedule(std::shared_ptr<SimulatedMessage> message);
 
-  void HandleEvent();
+  void HandleEvent() noexcept;
 
   void SetSimulatedChannel(SimulatedChannel *channel) {
     simulated_channel_ = channel;
@@ -473,7 +473,7 @@
   void Setup(monotonic_clock::time_point base,
              monotonic_clock::duration repeat_offset) override;
 
-  void HandleEvent();
+  void HandleEvent() noexcept;
 
   void Disable() override;
 
@@ -496,7 +496,7 @@
                              const monotonic_clock::duration offset);
   ~SimulatedPhasedLoopHandler();
 
-  void HandleEvent();
+  void HandleEvent() noexcept;
 
   void Schedule(monotonic_clock::time_point sleep_time) override;
 
@@ -840,7 +840,7 @@
   msgs_.emplace_back(message);
 }
 
-void SimulatedWatcher::HandleEvent() {
+void SimulatedWatcher::HandleEvent() noexcept {
   const monotonic_clock::time_point monotonic_now =
       simulated_event_loop_->monotonic_now();
   VLOG(1) << simulated_event_loop_->distributed_now() << " "
@@ -1094,7 +1094,7 @@
   simulated_event_loop_->AddEvent(&event_);
 }
 
-void SimulatedTimerHandler::HandleEvent() {
+void SimulatedTimerHandler::HandleEvent() noexcept {
   const monotonic_clock::time_point monotonic_now =
       simulated_event_loop_->monotonic_now();
   VLOG(1) << simulated_event_loop_->distributed_now() << " "
@@ -1152,7 +1152,7 @@
   simulated_event_loop_->RemoveEvent(&event_);
 }
 
-void SimulatedPhasedLoopHandler::HandleEvent() {
+void SimulatedPhasedLoopHandler::HandleEvent() noexcept {
   monotonic_clock::time_point monotonic_now =
       simulated_event_loop_->monotonic_now();
   VLOG(1) << monotonic_now << " Phased loop " << simulated_event_loop_->name()