I dug into this briefly last week but couldn't fix it quickly. Naive application of white-space: nowrap (at least the way I did it) was apparently insufficient.

I just tried messing with this. It looks like using both: 

white-space: nowrap;
overflow: hidden;

seemed to do the trick for me? 

All you :) 

The following revision refers to this bug:
  https://chromium.googlesource.com/infra/infra.git/+/71259a85eb65b09ec2305e319f83f5f3117cde8a

commit 71259a85eb65b09ec2305e319f83f5f3117cde8a
Author: Tiffany Zhang <zhangtiff@chromium.org>
Date: Thu Aug 11 17:24:47 2016

SoM: Prevent linked bugs from wrapping.

BUG= 636664 

Change-Id: I2abac290db6d9ec8b6fc91f8811888a9b07d95a2
Reviewed-on: https://chromium-review.googlesource.com/367932
Reviewed-by: Stephen Martinis <martiniss@chromium.org>
Commit-Queue: Tiffany Zhang <zhangtiff@chromium.org>

[modify] https://crrev.com/71259a85eb65b09ec2305e319f83f5f3117cde8a/go/src/infra/appengine/sheriff-o-matic/elements/som-alert-item.html

This is fixed, no?

Fixed and merged but not yet deployed to staging. :)