I am working towards a fix for this, so I will take ownership unless you all have someone else in mind.

For reference : https://chromium-review.googlesource.com/c/chromium/src/+/1265822

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/7ed6beda453e6a8bb29aea298a9bf841e8434e5b

commit 7ed6beda453e6a8bb29aea298a9bf841e8434e5b
Author: Alexander Nohe <nohe@chromium.org>
Date: Wed Oct 10 03:07:52 2018

Unnecessary play option for one image in slideshow

Hiding the play / pause button in the slideshow when only one image
is loaded.  This is unnecessary since the one image will be loaded and
there is nothing to pause or play.

Initial Slideshow fix and tests

Bug:  717482 
Change-Id: Iba7f74d4237ac46405be5cc7cabfd92f7a177f00
Reviewed-on: https://chromium-review.googlesource.com/c/1265822
Reviewed-by: Noel Gordon <noel@chromium.org>
Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Commit-Queue: Noel Gordon <noel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#598195}
[modify] https://crrev.com/7ed6beda453e6a8bb29aea298a9bf841e8434e5b/chrome/browser/chromeos/file_manager/gallery_browsertest.cc
[modify] https://crrev.com/7ed6beda453e6a8bb29aea298a9bf841e8434e5b/ui/file_manager/gallery/js/slide_mode.js
[modify] https://crrev.com/7ed6beda453e6a8bb29aea298a9bf841e8434e5b/ui/file_manager/integration_tests/gallery/slideshow.js

Your change meets the bar and is auto-approved for M71. Please go ahead and merge the CL to branch 3578 manually. Please contact milestone owner if you have questions.
Owners: benmason@(Android), kariahda@(iOS), kbleicher@(ChromeOS), govind@(Desktop)

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