Restore maximized window position after detaching display.

Restore maximized window position after detaching display.

Sometimes Windows incorrectly changes bounds of maximized windows after
attaching or detaching additional displays. In this case user can see
non-client area of the window (that should be hidden in normal case).

This workaround code restores window position if problem occurs and also
fixes problem with broken shortcuts for changing monitor (Win+Shift+Left
or Win+Shift+Right) for maximized and fullscreen mode, caused by
incorrect same monitor detection logic in OnWindowPosChanging() (see
crbug.com/656001).

BUG=651449, 656001
Committed: https://crrev.com/306338a1ac90527e74f9604cd5b202d1cdf2cb63
Cr-Commit-Position: refs/heads/master@{#432156}

[atimoxin, 2016-11-09 16:11:24]

atimoxin@yandex-team.ru changed reviewers:
+ ananta@chromium.org, sky@chromium.org

[atimoxin, 2016-11-09 16:11:24]

This is a second attempt of landing patch from crrev.com/2379063003.

The problem described in crbug.com/656001 occured because of bug in same monitor
detection logic: when user presses change monitor shortcut, window receives
WM_WINDOWPOSCHANGING with rect (in parameter) located on other monitor, but we
use (in OnWindowPosChanging()) GetWindowRect() function (which returns rect on
current monitor) and then use GetMonitorAndRects() with this rect to determine
monitor and it's parameters. Consequently, we think that monitor isn't changed
(|same_monitor| variable) and apply our hacks for fullscreen and my new hack for
maximized window.

I changed this logic a bit, so we would use rect from message parameter (if any)
to determine monitor. This fixes shortcuts for maximized window and also for
window in fullscreen.

[sky, 2016-11-09 16:29:37]

Can you upload the two reverted patches as an early patch and the fix on top of
that? That way it's easy to see what changed.

Also, is it possible to test any of this? I don't believe we have any
multi-monitor test bots, so maybe not...

[atimoxin, 2016-11-14 17:51:15]

On 2016/11/09 16:29:37, sky wrote:
> Can you upload the two reverted patches as an early patch and the fix on top
of
> that? That way it's easy to see what changed.
> 
> Also, is it possible to test any of this? I don't believe we have any
> multi-monitor test bots, so maybe not...

Yes, of course. I uploaded reverted patches and new changes as separated patch
sets.

I think, it is dificult to write automatic tests for this issue, because it is a
workaround for a bug in window manager and it is really reproducible only in
specific hardware conditions (such as multi-monitor configuration). And also I
didn't find any test code for HWNDMessageHandler (maybe because it is very low
level and system specific code).

[sky, 2016-11-14 20:23:43]

Thanks for the new patches. LGTM

[atimoxin, 2016-11-15 09:15:49]

The CQ bit was checked by atimoxin@yandex-team.ru

[commit-bot: I haz the power, 2016-11-15 09:16:08]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-11-15 10:03:24]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-11-15 10:05:17]

Description was changed from

==========
Restore maximized window position after detaching display.

Sometimes Windows incorrectly changes bounds of maximized windows after
attaching or detaching additional displays. In this case user can see
non-client area of the window (that should be hidden in normal case).

This workaround code restores window position if problem occurs and also
fixes problem with broken shortcuts for changing monitor (Win+Shift+Left
or Win+Shift+Right) for maximized and fullscreen mode, caused by
incorrect same monitor detection logic in OnWindowPosChanging() (see
crbug.com/656001).

BUG=651449,656001
==========

to

==========
Restore maximized window position after detaching display.

Sometimes Windows incorrectly changes bounds of maximized windows after
attaching or detaching additional displays. In this case user can see
non-client area of the window (that should be hidden in normal case).

This workaround code restores window position if problem occurs and also
fixes problem with broken shortcuts for changing monitor (Win+Shift+Left
or Win+Shift+Right) for maximized and fullscreen mode, caused by
incorrect same monitor detection logic in OnWindowPosChanging() (see
crbug.com/656001).

BUG=651449,656001

Committed: https://crrev.com/306338a1ac90527e74f9604cd5b202d1cdf2cb63
Cr-Commit-Position: refs/heads/master@{#432156}
==========

[commit-bot: I haz the power, 2016-11-15 10:05:18]

Patchset 4 (id:??) landed as
https://crrev.com/306338a1ac90527e74f9604cd5b202d1cdf2cb63
Cr-Commit-Position: refs/heads/master@{#432156}