Issue is also seen in 53.0.2768.0/8459.0.0 of daisy,blaze,jerry.

Able to reproduce the issue on Blaze using chrome version 53.0.2768.0/8459.0.0

oka@: Could you take a look at this? Thank you!

This kind of FOUS also happens with Chrome.
1. Show a large image such as https://upload.wikimedia.org/wikipedia/commons/3/3d/LARGE_elevation.jpg on Chrome.
2. Maximize the window
Then white blink is seen.

So I think it's not Files App's problem.

I also found that flickering happens only for the first time after the app is opened. If you opens the app and then maximize, minimize and maximize the window, flickering doesn't happen for the second time.

fukino@, do you know to whom can I assign the issue?

I'm not sure which part is suspicious based on the current information.
Did you reproduce it on Linux?
If so, can you do bisection and assign this to the CL owner?

Discussed offline, the root cause will be on Blink. On our side, let's make
background black to mitigate the distraction of flash.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/56f5f878bfdfbdf30036b3d0ae5d03b42ff89048

commit 56f5f878bfdfbdf30036b3d0ae5d03b42ff89048
Author: oka <oka@chromium.org>
Date: Mon Jun 27 04:17:45 2016

Make body background black to mitigate flash on hitting full screen for gallery.

BUG= 620574 
TEST=none

Review-Url: https://codereview.chromium.org/2100723002
Cr-Commit-Position: refs/heads/master@{#402109}

[modify] https://crrev.com/56f5f878bfdfbdf30036b3d0ae5d03b42ff89048/ui/file_manager/gallery/css/gallery.css

ChromeOS build 8530.96.0 / 53.0.2785.154