Initializes some uninitialized class members of TrackRunIterator.

Bug: none
Change-Id: I3636b34d6f87f9db732f1263cc3f2eddeb39335f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1670527
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Reviewed-by: Chrome Cunningham <chcunningham@chromium.org>
Commit-Queue: Chrome Cunningham <chcunningham@chromium.org>
Cr-Commit-Position: refs/heads/master@{#671896}
1 file changed