[Worker] Test using FileWriterSync.seek to write overlapping existing data in a file.

On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".

Starting worker: ../resources/file-writer-sync-write-overlapped.js
PASS [Worker] Overlapped write 1 verified.
PASS [Worker] Overlapped write 2 verified.
PASS [Worker] Overlapped write 3 verified.
PASS successfullyParsed is true

TEST COMPLETE