shiny/screen: sanitize NewWindowOptions.Title.

Its bytes are passed to C libraries, so we sanitize as a precaution.

Change-Id: I6ecdd5388be40c4067815ba0484112bea6c55270
Reviewed-on: https://go-review.googlesource.com/37414
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
7 files changed