This is not limited to HALF launcher, hitting escape in the fullscreen launcher also does the same thing.

The search isn't required either, for instance you can reproduce by doing the following:

1. Open launcher.
2. Open fullscreen mode by dragging or pressing the all apps arrow.
3. Press escape once.

The launcher goes from full screen with all apps shown to full screen with only suggested apps shown (and the arrow reappears) so it's in the "peeking" state except the bounds haven't been updated.

Deleted: peekingbutfullscreen.png 315 KB

	peekingbutfullscreen.png 315 KB View Download

Clarifying the intended behaviour on these state transitions from UX.

For now https://chromium-review.googlesource.com/c/578733/ assumes that the behaviour should be the same as clicking on the background. i.e. the launcher should actually not go to PEEKING from FULLSCREEN at all.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/18da770d8e4781f5b08d14c6c2a4a56a43da54fa

commit 18da770d8e4781f5b08d14c6c2a4a56a43da54fa
Author: Maajid <maajid@chromium.org>
Date: Fri Jul 21 22:35:36 2017

Fix app list test that assumed that a nonempty searchbox should be
inactive. Even if there is only whitespace in the searchbox, it
should still be active. In addition, clearing the searchbox from
the app list view creates easy opportunities for infinite loops.

Bug:  740662 
Change-Id: I9806242ac448dfb7a2a0d2af34388aa3fa3c47d8
Reviewed-on: https://chromium-review.googlesource.com/581567
Commit-Queue: Maajid <maajid@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#488778}
[modify] https://crrev.com/18da770d8e4781f5b08d14c6c2a4a56a43da54fa/ash/app_list/app_list_presenter_delegate_unittest.cc
[modify] https://crrev.com/18da770d8e4781f5b08d14c6c2a4a56a43da54fa/ui/app_list/views/app_list_view.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/708874ac3d1135aff5c556d3c3f2a9f18af248b9

commit 708874ac3d1135aff5c556d3c3f2a9f18af248b9
Author: Maajid <maajid@chromium.org>
Date: Tue Jul 25 00:03:57 2017

Fix state transition bugs when pressing the escape key for the fullscreen app list.
After this change, if escape is pressed, the following state changes occur:
PEEKING->CLOSED
HALF->PEEKING
FULLSCREEN_ALL_APPS->CLOSED
FULLSCREEN_SEARCH->FULLSCREEN_ALL_APPS

Bug:  740662 
Test: Unit tested, device tested with --enable-features=EnableFullscreenAppList
Change-Id: Id0820a9f07bf362fddc6e1adb3ef5648b3d2070d
Reviewed-on: https://chromium-review.googlesource.com/578733
Commit-Queue: Maajid <maajid@chromium.org>
Reviewed-by: Yury Khmel <khmel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#489151}
[modify] https://crrev.com/708874ac3d1135aff5c556d3c3f2a9f18af248b9/ui/app_list/views/app_list_view.cc
[modify] https://crrev.com/708874ac3d1135aff5c556d3c3f2a9f18af248b9/ui/app_list/views/app_list_view.h
[modify] https://crrev.com/708874ac3d1135aff5c556d3c3f2a9f18af248b9/ui/app_list/views/app_list_view_unittest.cc
[modify] https://crrev.com/708874ac3d1135aff5c556d3c3f2a9f18af248b9/ui/app_list/views/contents_view.cc
[modify] https://crrev.com/708874ac3d1135aff5c556d3c3f2a9f18af248b9/ui/app_list/views/search_box_view.cc

Your change meets the bar and is auto-approved for M61. Please go ahead and merge the CL to branch 3163 manually. Please contact milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), ketakid @(ChromeOS), govind@(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/+/d6ea54be4dda0ab285c194a931e3586138b8007c

commit d6ea54be4dda0ab285c194a931e3586138b8007c
Author: Maajid <maajid@chromium.org>
Date: Thu Jul 27 18:33:41 2017

Fix app list test that assumed that a nonempty searchbox should be inactive. Even if there is only whitespace in the searchbox, it should still be active. In addition, clearing the searchbox from the app list view creates easy opportunities for infinite loops.

TBR=maajid@chromium.org

(cherry picked from commit 18da770d8e4781f5b08d14c6c2a4a56a43da54fa)

Bug:  740662 
Change-Id: I9806242ac448dfb7a2a0d2af34388aa3fa3c47d8
Reviewed-on: https://chromium-review.googlesource.com/581567
Commit-Queue: Maajid <maajid@chromium.org>
Reviewed-by: Scott Violet <sky@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#488778}
Reviewed-on: https://chromium-review.googlesource.com/590093
Reviewed-by: Vadim Tryshev <vadimt@chromium.org>
Cr-Commit-Position: refs/branch-heads/3163@{#88}
Cr-Branched-From: ff259bab28b35d242e10186cd63af7ed404fae0d-refs/heads/master@{#488528}
[modify] https://crrev.com/d6ea54be4dda0ab285c194a931e3586138b8007c/ash/app_list/app_list_presenter_delegate_unittest.cc
[modify] https://crrev.com/d6ea54be4dda0ab285c194a931e3586138b8007c/ui/app_list/views/app_list_view.cc

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/3fbeae8a673ce16aa2ec63ee301516bba4dd8895

commit 3fbeae8a673ce16aa2ec63ee301516bba4dd8895
Author: Maajid <maajid@chromium.org>
Date: Thu Jul 27 18:45:22 2017

Fix state transition bugs when pressing the escape key for the fullscreen app list. After this change, if escape is pressed, the following state changes occur: PEEKING->CLOSED HALF->PEEKING FULLSCREEN_ALL_APPS->CLOSED FULLSCREEN_SEARCH->FULLSCREEN_ALL_APPS

TBR=maajid@chromium.org

(cherry picked from commit 708874ac3d1135aff5c556d3c3f2a9f18af248b9)

Bug:  740662 
Test: Unit tested, device tested with --enable-features=EnableFullscreenAppList
Change-Id: Id0820a9f07bf362fddc6e1adb3ef5648b3d2070d
Reviewed-on: https://chromium-review.googlesource.com/578733
Commit-Queue: Maajid <maajid@chromium.org>
Reviewed-by: Yury Khmel <khmel@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#489151}
Reviewed-on: https://chromium-review.googlesource.com/590527
Reviewed-by: Vadim Tryshev <vadimt@chromium.org>
Cr-Commit-Position: refs/branch-heads/3163@{#91}
Cr-Branched-From: ff259bab28b35d242e10186cd63af7ed404fae0d-refs/heads/master@{#488528}
[modify] https://crrev.com/3fbeae8a673ce16aa2ec63ee301516bba4dd8895/ui/app_list/views/app_list_view.cc
[modify] https://crrev.com/3fbeae8a673ce16aa2ec63ee301516bba4dd8895/ui/app_list/views/app_list_view.h
[modify] https://crrev.com/3fbeae8a673ce16aa2ec63ee301516bba4dd8895/ui/app_list/views/app_list_view_unittest.cc
[modify] https://crrev.com/3fbeae8a673ce16aa2ec63ee301516bba4dd8895/ui/app_list/views/contents_view.cc
[modify] https://crrev.com/3fbeae8a673ce16aa2ec63ee301516bba4dd8895/ui/app_list/views/search_box_view.cc