Don't lose title/fileinfo tracking on diff view

When introducing the title/fileinfo edit tracking dragging the stats
was forgotten here. This is fixed with that change.

See original patch I578b51a8d6fb8f6af21ed887589a477bc59d8fd2
Bug: T225611

Change-Id: Ic6c465ee4089f996cdeeebc903fc9b76defc02fa