The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ebb057907a7021a089e42a5d51d77a16558c4f24

commit ebb057907a7021a089e42a5d51d77a16558c4f24
Author: James Cook <jamescook@chromium.org>
Date: Tue Sep 26 00:10:07 2017

cros: Fix fullscreen app list under mash

* Place app list widget in the ash app list window container, instead of
  in the container for browser windows.
* Perform widget bounds computations in local coordinates. This avoids
  problems with screen-to-local computations under mash where the native
  window's parent is the desktop widget, not the window container as in
  classic ash.
* Use side shelf mode in mash, which skips some problematic opening
  animations. See  issue 768437 .
* Introduce AppListView::InitParams so we don't have 2 ints and 2 bools
  as adjacent parameters.
* Eliminate some unused Init() method params.

Bug:  763961 ,  768437 
Test: app_list_unittests, manual testing of fullscreen app list with multiple monitors (stacked vertically) and/or side shelf mode.

Change-Id: I933f5130feab3d8b4edfc2b573f52748e9c82539
Reviewed-on: https://chromium-review.googlesource.com/682343
Commit-Queue: James Cook <jamescook@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#504226}
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ash/app_list/app_list_presenter_delegate.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/chrome/browser/ui/ash/app_list/app_list_presenter_delegate_mus.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/BUILD.gn
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/DEPS
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/presenter/app_list_presenter_impl_unittest.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/app_list_main_view.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/app_list_main_view.h
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/app_list_main_view_unittest.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/app_list_view.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/app_list_view.h
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/app_list_view_unittest.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/apps_grid_view_unittest.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/search_box_view_unittest.cc
[modify] https://crrev.com/ebb057907a7021a089e42a5d51d77a16558c4f24/ui/app_list/views/search_result_page_view_unittest.cc

Alex, I'm just going to assign this to you so it has an owner. There's nothing urgent to do here.

Sounds good. Thanks James!

TechDebt

Added to techdebt hotlist, thanks shiba.

Removing myself as owner so we can assign this via the launcher triage process.

I'm currently looking into having the widget start as fullscreen/transformed offscreen, then transforming it into position. I think this is the last detail this bug is waiting for, so I'll use it as a tracker for that task. Please let me know if this doesn't sound correct!

Alex, Let me know if the priorities / milestones are correct, I updated them according to what we discussed offline.

I believe you've done this already when you reworked App List to use transform?

I think what we are doing is the same as described in #12: https://cs.chromium.org/chromium/src/ash/app_list/views/app_list_view.cc?q=app_list_view.cc&sq=package:chromium&g=0&l=1216