Improve check for whether _NET_ACTIVE_WINDOW is supported

Make check for whether _NET_ACTIVE_WINDOW is supported take into account _NET_SUPPORTED and _NET_SUPPORTING_WM_CHECK

BUG=416490
TEST=Manual

Committed: https://crrev.com/2973ee193b002e66a29d9a082520a3d88bb7a119
Cr-Commit-Position: refs/heads/master@{#296226}

[pkotwicz, 2014-09-22 23:08:52]

Patchset #1 (id:1) has been deleted

[pkotwicz, 2014-09-22 23:16:21]

pkotwicz@chromium.org changed reviewers:
+ derat@chromium.org

[pkotwicz, 2014-09-22 23:16:22]

derat@ PTAL

Full disclosure, I have not tested on xmonad. I have tested on Unity. I
installed xmonad and _NET_SUPPORTED is not set on the root window for me. This
CL should fix the bug based on the output provided by Istiaque in comment #9 on
the bug

[Daniel Erat, 2014-09-23 15:32:41]

just to make sure my understanding is correct: xmonad (at least per
http://crbug.com/416490#c9) claims that it supports _NET_ACTIVE_WINDOW via
_NET_SUPPORTED but isn't setting _NET_SUPPORTING_WM_CHECK (which is also
required by EWMH).

this change makes us stop believing that it supports _NET_ACTIVE_WINDOW (since
its EWMH support seems incomplete) and instead use FocusIn/FocusOut events,
right?

if so, lgtm. but lazyboy@, mind testing this in a local build first so we can
make that sure it resolves the issue?

https://codereview.chromium.org/591213004/diff/20001/ui/base/x/x11_util.cc
File ui/base/x/x11_util.cc (right):

https://codereview.chromium.org/591213004/diff/20001/ui/base/x/x11_util.cc#ne...
ui/base/x/x11_util.cc:107: static bool supports_ewmh_cached = false;
i was going to say that i'm not sure how i feel about caching this (what if the
window manager is replaced?), but i guess we were already getting this wrong by
caching whether _NET_ACTIVE_WINDOW is supported, so it's not a huge deal. :-/

i think that the right fix here would be to watch for _NET_SUPPORTING_WM_CHECK
property changes on the root window (see e.g. X11DesktopHandler's monitoring of
PropertyNotify events on the root for _NET_ACTIVE_WINDOW), but it's probably not
worth the effort.

[pkotwicz, 2014-09-23 15:39:51]

pkotwicz@chromium.org changed reviewers:
+ lazyboy@chromium.org

[pkotwicz, 2014-09-23 15:39:52]

lazyboy@ do you mind testing that this CL fixes things for you?

[lazyboy, 2014-09-23 16:10:09]

On 2014/09/23 15:39:52, pkotwicz wrote:
> lazyboy@ do you mind testing that this CL fixes things for you?

Yes!

[Daniel Erat, 2014-09-23 16:10:57]

On 2014/09/23 16:10:09, lazyboy wrote:
> On 2014/09/23 15:39:52, pkotwicz wrote:
> > lazyboy@ do you mind testing that this CL fixes things for you?
> 
> Yes!

thanks, i'm trying this out on ion3 as well.

[Daniel Erat, 2014-09-23 16:32:18]

On 2014/09/23 16:10:57, Daniel Erat wrote:
> On 2014/09/23 16:10:09, lazyboy wrote:
> > On 2014/09/23 15:39:52, pkotwicz wrote:
> > > lazyboy@ do you mind testing that this CL fixes things for you?
> > 
> > Yes!
> 
> thanks, i'm trying this out on ion3 as well.

seems fine on ion3 (which sets _NET_SUPPORTING_WM_CHECK in addition to claiming
support for _NET_ACTIVE_WINDOW via _NET_SUPPORTED), so still lgtm

[pkotwicz, 2014-09-23 16:44:19]

The CQ bit was checked by pkotwicz@chromium.org

[commit-bot: I haz the power, 2014-09-23 16:45:49]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/591213004/20001

[commit-bot: I haz the power, 2014-09-23 16:56:44]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2014-09-23 16:56:45]

Try jobs failed on following builders:
  chromium_presubmit on tryserver.chromium.linux
(http://build.chromium.org/p/tryserver.chromium.linux/builders/chromium_presub...)

[pkotwicz, 2014-09-23 17:59:39]

pkotwicz@chromium.org changed reviewers:
+ erg@chromium.org

[pkotwicz, 2014-09-23 17:59:39]

erg@ for ui/views/ OWNERS

[Elliot Glaysher, 2014-09-23 18:04:10]

lgtm

[pkotwicz, 2014-09-23 19:38:24]

The CQ bit was checked by pkotwicz@chromium.org

[commit-bot: I haz the power, 2014-09-23 20:30:38]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/591213004/20001

[commit-bot: I haz the power, 2014-09-23 20:47:49]

Committed patchset #1 (id:20001) as a82484e8d7ecb56df8b30fd0da5fedf65c95e939

[commit-bot: I haz the power, 2014-09-23 20:48:54]

Patchset 1 (id:??) landed as
https://crrev.com/2973ee193b002e66a29d9a082520a3d88bb7a119
Cr-Commit-Position: refs/heads/master@{#296226}