GitLab

Regardless of where the highlight position is, after switching
alt-tab mode, the highlight will be reset to the first or second
window. This is consistent with highlighting when users first
enter alt-tab mode:
- In general case, highlight the second (next) most recently used
window after the current one.
- In the special case that the most recently used is minimized,
highlight itself (the MRU window), so tabbing into it causes it
to unminimize rather than opening up the next window in the list.

- Track mode switching state in the controller to differentiate
between normal tab pressing and mode switching.
- Add Ash unit tests for both cases.

`ash_unittests --gtest_filter=ModeSelectionWindowCycleControllerTest.SwitchingModeUpdates*WindowHighlight`

Bug: 1157100
Test: Manual test (a video uploaded to crbug) and ash unit tests
Change-Id: Id85b389ba9d59eb1815b8250d640e5aa9128240b
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2604907Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Reviewed-by: Min Chen <minch@chromium.org>
Commit-Queue: Cattalyya Nuengsigkapian <cattalyya@chromium.org>
Cr-Commit-Position: refs/heads/master@{#840348}