This is working as intended, the launcher is always accessible by swiping up from the bottom of the screen. 

Why do you not want the launcher to show up?

We do not want students to access anything when they're in the kiosk mode. 

Oh, thanks. I mis-read this as tablet mode. 

Thanks for filing. Raising priority. 

After reproducing this, the user will not be able to launch any apps or search from the launcher in kiosk mode. 

They will be able to see the launcher and the searchbox, but the launcher silently fails to launch apps/search.

We will still patch this in M67.

After doing a git bisect The error was tracked to this cl:
https://chromium-review.googlesource.com/c/chromium/src/+/954355

xiyuan, while hejq@ is OOO could you take a look?

The CL maybe the trigger of the bug but it is not the root cause.

The problem has two causes:
1. Shelf auto hide behavior is changed in ShelfController [1] when tablet
   mode starts, regardless of kiosk mode;
2. When tablet mode starts, TabletModeWindowManager kicks in and replaces
   window state with a TabletModeWindowState which does not reflect full screen
   state correctly (looks like it thinks the app window is an immersive
   maximized one).

1 is easy to fix. Not sure how 2 should be addressed, maybe disable tablet mode for kiosk.

[1] https://cs.chromium.org/chromium/src/ash/shelf/shelf_controller.cc?rcl=7ceb20aa2d291781ab6b0c9a2b0c3a2f44cf0581&l=336

Proposed fix:
  https://chromium-review.googlesource.com/c/chromium/src/+/1035522

Item 2 in #10 is because app window enables immersive mode when entering tablet mode. It works as expected if app window does not enable immersive mode.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/645b928b86c3b6ddaf4a9e1f8339cf7c18278b24

commit 645b928b86c3b6ddaf4a9e1f8339cf7c18278b24
Author: Xiyuan Xia <xiyuan@chromium.org>
Date: Tue May 01 23:20:32 2018

kiosk: No shelf/launcher in tablet mode

- Shelf stays with SHELF_AUTO_HIDE_ALWAYS_HIDDEN in tablet mode when
  running in a kiosk session;
- App window keeps the immersive mode disabled when entering tablet
  mode in a kiosk session;

Bug:  834058 
Test: ash_unittests ShelfControllerAppModeTest.AutoHideBehavior and browser_tests ChromeNativeAppWindowViewsAuraAshBrowserTest.NoImmersiveModeWhenForcedFullscreen
Change-Id: I57cf9ac08fdc48c433dcb0d5c3f7c561041431c3
Reviewed-on: https://chromium-review.googlesource.com/1035522
Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: Ben Wells <benwells@chromium.org>
Commit-Queue: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#555222}
[modify] https://crrev.com/645b928b86c3b6ddaf4a9e1f8339cf7c18278b24/ash/shelf/shelf_controller.cc
[modify] https://crrev.com/645b928b86c3b6ddaf4a9e1f8339cf7c18278b24/ash/shelf/shelf_controller_unittest.cc
[modify] https://crrev.com/645b928b86c3b6ddaf4a9e1f8339cf7c18278b24/chrome/browser/ui/views/apps/chrome_native_app_window_views_aura_ash.cc
[modify] https://crrev.com/645b928b86c3b6ddaf4a9e1f8339cf7c18278b24/chrome/browser/ui/views/apps/chrome_native_app_window_views_aura_ash.h
[modify] https://crrev.com/645b928b86c3b6ddaf4a9e1f8339cf7c18278b24/chrome/browser/ui/views/apps/chrome_native_app_window_views_aura_ash_browsertest.cc

This is a relatively large change for a late-cycle merge and it was occurring prior to M67 (reported for M65).  Rejecting for M67; please update and retag with scope / impact if disagree.  Thanks

+atwilson fyi

This has been broken for a while since tablet mode is added (probably as early as M62). Put it to M68.

Naveen: FYI - looks innocuous but wanted to loop you in.

Thanks Drew. Is the issue that this fix can't be made in 67? And that will lead to launcher and search being visible but not usable in 67 until this can be fixed in 68?