Edited Issue: editor tabs navigated to via 'go to to definition' close unexpectedly on next launch of VS [1707]

1) Create a new console project
2) code:
```
var async = require('async')
async.all
```

3) no need to complete the statement. F12 on parallel, and go to the definition, which takes you to the code in async.js
4) save project and close VS
5) open project, it'll open with async.js tab
6) click to navigate back to 'async.js' tab
7) save, close project, open project. async.js and app.js will be open.
8) click on the async.js tab, and it'll close unexpectedly.