Accidentally tried to print the colour '-1' if there was no line colour
set yet but the current colour had changed.

Bug: v8:7700
Change-Id: Iba3cbe51fd0e31e389e614d0a42e59147a51b902
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3859355
Commit-Queue: Victor Gomes <victorgomes@chromium.org>
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82789}