update tern and acorn to latest master
Update expected results, as Tern now gives us better results than what the test was expecting.
Merge pull request #4439 from eztierney/tern-investigation

Update tern & acorn
Untitled document support using InaccessibleFileEntry objects.
Merge pull request #4443 from adobe/untitled-documents

Untitled document support
per pull request review, updating comment and merging latest master (to manually resolve conflicts)