tiff: remove InternalError which is not used anywhere.

Change-Id: I92fd800bafd380797651e158c9385dcf3d3578da
Reviewed-on: https://go-review.googlesource.com/40892
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
1 file changed