Add runtime events for pause,resume,checkpoint

Fixes #1068

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

linux/shim/service.go

@@ -283,6 +283,12 @@ func (s *Service) Pause(ctx context.Context, r *google_protobuf.Empty) (*google_
 	if err := s.initProcess.Pause(ctx); err != nil {
 		return nil, err
 	}
+	s.events <- &events.RuntimeEvent{
+		Type:        events.RuntimeEvent_PAUSED,
+		ID:          s.id,
+		ContainerID: s.id,
+		Timestamp:   time.Now(),
+	}
 	return empty, nil
 }
 
@@ -293,6 +299,12 @@ func (s *Service) Resume(ctx context.Context, r *google_protobuf.Empty) (*google
 	if err := s.initProcess.Resume(ctx); err != nil {
 		return nil, err
 	}
+	s.events <- &events.RuntimeEvent{
+		Type:        events.RuntimeEvent_RESUMED,
+		ID:          s.id,
+		ContainerID: s.id,
+		Timestamp:   time.Now(),
+	}
 	return empty, nil
 }
 
@@ -344,6 +356,12 @@ func (s *Service) Checkpoint(ctx context.Context, r *shimapi.CheckpointTaskReque
 	if err := s.initProcess.Checkpoint(ctx, r); err != nil {
 		return nil, err
 	}
+	s.events <- &events.RuntimeEvent{
+		Type:        events.RuntimeEvent_CHECKPOINTED,
+		ID:          s.id,
+		ContainerID: s.id,
+		Timestamp:   time.Now(),
+	}
 	return empty, nil
 }