fix(MesosStateStore): adjust stream data handling

Use `Promise.resolve().then()` to trigger the stream subscription asynchronously on the same macrotask (by using a microtask). Events emitted by the strean, trigger `onStreamData` which is used to emit an event (using EventEmitter) called `MESOS_STATE_CHANGE`. This change will mitigate issues in which errors in view components lead to stale data because the error propagation broke the stream.

N.B. `EventEmitter` is synchronous meaning that every delay in an event handler effects the `emit` execution time and errors propagate up to the `emit` call which sometimes leads to undesireable behavior.

Closes DCOS-21784

src/js/stores/MesosStateStore.js

@@ -56,7 +56,7 @@ class MesosStateStore extends GetSetBaseStore {
     this.on(eventName, callback);
 
     if (this.shouldSubscribe()) {
-      this.subscribe();
+      Promise.resolve().then(() => this.subscribe());
     }
   }
 
@@ -99,7 +99,8 @@ class MesosStateStore extends GetSetBaseStore {
     // refresh limits to the UI. They are:
     //
     // MOST once every (Config.getRefreshRate() * 0.5) ms. due to debounceTime.
-    // LEAST once every tick of Config.getRefreshRate() ms in Observable.interval
+    // LEAST once every tick of Config.getRefreshRate() ms in
+    // Observable.interval
     //
     // TODO: https://jira.mesosphere.com/browse/DCOS-18277
     this.stream = waitStream