Fixed flow error about require platform forked component

Summary:Commit 29e6bac introduced a flow break in e2e tests.
This commit fixes float.

**Test plan (required)**

```bash
flow check Libraries
npm test
```

Make sure JS tests pass on TravisCI.
Closes facebook#6168

Differential Revision: D2982108

fb-gh-sync-id: 0aea38f7b7e00c7ce91284e7ca6a01318792cc75
shipit-source-id: 0aea38f7b7e00c7ce91284e7ca6a01318792cc75

Examples/UIExplorer/UIExplorerStateTitleMap.js

@@ -15,6 +15,7 @@
  */
 'use strict';
 
+// $FlowFixMe : This is a platform-forked component, and flow seems to only run on iOS?
 const UIExplorerList = require('./UIExplorerList');
 
 import type {NavigationState} from 'NavigationStateUtils';