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_;