add comment for the test

Author: podviaznikov

lib/models/events/docker.js

@@ -117,6 +117,8 @@ DockerEvents.prototype.handleDie = function (data) {
   debug('handleDie', arguments);
   // this api is closing and will not handle any new events.
   if (this.closeHandler) {
+    // this debug statement is covered with unit test. Don't change/remove it.
+    // see unit/docker-events.js
     return debug('events are stopping');
   }
   var self = this;
@@ -131,7 +133,11 @@ DockerEvents.prototype.handleDie = function (data) {
   var containerId = data.id;
   activeApi.isMe(function (err, meIsActiveApi) {
     if (err) { return logErr(err); }
-    if (!meIsActiveApi) { return debug('not active api'); }
+    if (!meIsActiveApi) {
+      // this debug statement is covered with unit test. Don't change/remove it.
+      // see unit/docker-events.js
+      return debug('not active api');
+    }
     self.getEventLock(data.uuid, function (err, eventMutex) {
       if (err) { return logErr(err); }
       var userStoppedContainer = new UserStoppedContainer(containerId);