[TxMt] repeatable crasher: Have jump to symbol window open...

[Tim Bates]

1. Open ⌘⇧-T window
2. Open a file that takes some time to syntax highlight

Expected: newly opened file highlights, and function window populates
Obtained: Spinning wheel of death

Alternative repro

1. Open a file that takes some time to syntax highlight
2. Open ⌘⇧-T window (you probably have a few seconds to do this)

Expected: Function window populates with function list
Obtained: Spinning wheel of death


Version: 2.0-rc.7.