For M-70, maybe we should just hide the Files app's disk space stat from the 3-dot menu. We should also hide the storage management part of chrome://settings.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/d5622364f53fdec4e8e82373e2190d94cdb14e97

commit d5622364f53fdec4e8e82373e2190d94cdb14e97
Author: Wenzhao Zang <wzang@chromium.org>
Date: Tue Aug 28 04:06:34 2018

cros: Hide storage management in settings during demo session

Bug:  868747 
Change-Id: Id936d7570ba33041d817a30534d6479e42718fd1
Reviewed-on: https://chromium-review.googlesource.com/1192345
Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Commit-Queue: Wenzhao (Colin) Zang <wzang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#586576}
[modify] https://crrev.com/d5622364f53fdec4e8e82373e2190d94cdb14e97/chrome/browser/resources/settings/device_page/device_page.html
[modify] https://crrev.com/d5622364f53fdec4e8e82373e2190d94cdb14e97/chrome/browser/resources/settings/device_page/device_page.js
[modify] https://crrev.com/d5622364f53fdec4e8e82373e2190d94cdb14e97/chrome/browser/ui/webui/settings/md_settings_ui.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/09393b820f8a539a1d2019817672e96f3d64b68a

commit 09393b820f8a539a1d2019817672e96f3d64b68a
Author: Wenzhao Zang <wzang@chromium.org>
Date: Fri Aug 31 04:30:57 2018

cros: Hide space info in Files app during demo session

The space info button in the Files app redirects to the “Storage
management” section in Settings, which has already been hidden in Demo
Mode. So it makes sense to hide this button as well.

In Demo Mode (a public session), the cryptohome runs in RAM. As a
result, the Files app only considers available RAM when showing free
disk space. Therefore, customers in stores might think the device only
has 4 GB of disk space.

We should hide the disk space stat until there's a better solution,
e.g. show an explanatory message ("disk space is limited in Demo Mode"
or something).

Bug:  868747 
Change-Id: I8b138bbf0b864acaf38a51659cccf7ad3d198c16
Reviewed-on: https://chromium-review.googlesource.com/1198882
Reviewed-by: Naoki Fukino <fukino@chromium.org>
Commit-Queue: Wenzhao (Colin) Zang <wzang@chromium.org>
Cr-Commit-Position: refs/heads/master@{#587942}
[modify] https://crrev.com/09393b820f8a539a1d2019817672e96f3d64b68a/chrome/browser/chromeos/extensions/file_manager/private_api_strings.cc
[modify] https://crrev.com/09393b820f8a539a1d2019817672e96f3d64b68a/ui/file_manager/file_manager/foreground/js/ui/gear_menu.js

Merge request for CL in #4.

Your change meets the bar and is auto-approved for M70. Please go ahead and merge the CL to branch 3538 manually. Please contact milestone owner if you have questions.
Owners: benmason@(Android), kariahda@(iOS), geohsu@(ChromeOS), abdulsyed@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/4005c97c13a2d6dd3677b6f2202296ab57e44bd3

commit 4005c97c13a2d6dd3677b6f2202296ab57e44bd3
Author: Wenzhao Zang <wzang@chromium.org>
Date: Wed Sep 05 22:07:52 2018

[Merge to M70] cros: Hide space info in Files app during demo session

The space info button in the Files app redirects to the “Storage
management” section in Settings, which has already been hidden in Demo
Mode. So it makes sense to hide this button as well.

In Demo Mode (a public session), the cryptohome runs in RAM. As a
result, the Files app only considers available RAM when showing free
disk space. Therefore, customers in stores might think the device only
has 4 GB of disk space.

We should hide the disk space stat until there's a better solution,
e.g. show an explanatory message ("disk space is limited in Demo Mode"
or something).

TBR=wzang@chromium.org

(cherry picked from commit 09393b820f8a539a1d2019817672e96f3d64b68a)

Bug:  868747 
Change-Id: I8b138bbf0b864acaf38a51659cccf7ad3d198c16
Reviewed-on: https://chromium-review.googlesource.com/1198882
Reviewed-by: Naoki Fukino <fukino@chromium.org>
Commit-Queue: Wenzhao (Colin) Zang <wzang@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#587942}
Reviewed-on: https://chromium-review.googlesource.com/1208815
Reviewed-by: Wenzhao (Colin) Zang <wzang@chromium.org>
Cr-Commit-Position: refs/branch-heads/3538@{#71}
Cr-Branched-From: 79f7c91a2b2a2932cd447fa6f865cb6662fa8fa6-refs/heads/master@{#587811}
[modify] https://crrev.com/4005c97c13a2d6dd3677b6f2202296ab57e44bd3/chrome/browser/chromeos/extensions/file_manager/private_api_strings.cc
[modify] https://crrev.com/4005c97c13a2d6dd3677b6f2202296ab57e44bd3/ui/file_manager/file_manager/foreground/js/ui/gear_menu.js

The free space stats is hidden. Please reopen the bug if we want explanatory texts instead.