Fix releasing capture in Ozone

Fix releasing capture in Ozone

In CrOS Ozone, WindowTreeHost::SetCapture() is not a no-op (unlike CrOS X11).
This CL makes CaptureController::SetCapture() release capture on the
WindowTreeHost which has native capture regardless of which WindowTreeHost
the aura::Window with capture is currently in.

BUG=423383
TEST=None

Committed: https://crrev.com/2865fb61212f41f2f1f605a018e6a8d3e53e6100
Cr-Commit-Position: refs/heads/master@{#308649}

[pkotwicz, 2014-12-05 21:27:54]

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

[pkotwicz, 2014-12-05 21:29:49]

pkotwicz@chromium.org changed reviewers:
- sadrul@chromium.org

[pkotwicz, 2014-12-05 21:34:07]

Patchset #1 (id:1) has been deleted

[pkotwicz, 2014-12-06 04:20:15]

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

[pkotwicz, 2014-12-06 04:20:16]

Sadrul, PTAL

As discussed offline, it is unclear whether CrOS (ozone or not) should do native
capture
However, Windows should do native capture.
AshRemoteWindowTreeHostWin::SetCapture() is currently a no-op and there are bugs
due to this. (e.g. press mouse button, then press Ctrl+Alt+Delete to get lock
screen without releasing mouse button)

[pkotwicz, 2014-12-08 19:39:35]

Patchset #2 (id:30001) has been deleted

[sadrul, 2014-12-11 15:11:00]

Please fix BUG in the CL description.

https://codereview.chromium.org/780273003/diff/10003/ui/wm/core/capture_contr...
File ui/wm/core/capture_controller.cc (right):

https://codereview.chromium.org/780273003/diff/10003/ui/wm/core/capture_contr...
ui/wm/core/capture_controller.cc:57: capture_window_ ?
capture_window_->GetRootWindow() : NULL;
nullptr

https://codereview.chromium.org/780273003/diff/10003/ui/wm/core/capture_contr...
ui/wm/core/capture_controller.cc:58: capture_delegate_ = capture_root_window
Can |capture_delegate| be a local variable instead?

https://codereview.chromium.org/780273003/diff/10003/ui/wm/core/capture_contr...
ui/wm/core/capture_controller.cc:72: capture_delegate_->SetNativeCapture();
The old code makes much more sense when reading than the new code. Can you
explain how this is different from the old code?

[pkotwicz, 2014-12-11 16:22:49]

https://codereview.chromium.org/780273003/diff/10003/ui/wm/core/capture_contr...
File ui/wm/core/capture_controller.cc (right):

https://codereview.chromium.org/780273003/diff/10003/ui/wm/core/capture_contr...
ui/wm/core/capture_controller.cc:72: capture_delegate_->SetNativeCapture();
If a window with capture is reparented to a different WindowTreeHost, native
capture is NOT set on the new WindowTreeHost (or released from the old
WindowTreeHost)

When capture is released, native capture should be released from the
WindowTreeHost with capture
The old code assumed that "the WindowTreeHost with capture" is the same as the
WindowTreeHost containing |capture_window_|

In the email that I sent out on Sunday, I described why setting native capture
in WindowTreeHostOzone is unnecessary. However, we cannot remove the calls for
setting native capture here because of Windows Ash (which has bugs because it
does not set native capture)

[pkotwicz, 2014-12-12 23:50:39]

Patchset #2 (id:50001) has been deleted

[pkotwicz, 2014-12-12 23:51:59]

Patchset #2 (id:70001) has been deleted

[pkotwicz, 2014-12-13 00:02:58]

Sadrul, can you please take another look?
I have added a unit test as you requested

[sadrul, 2014-12-16 15:24:13]

LGTM

https://codereview.chromium.org/780273003/diff/90001/ui/wm/core/capture_contr...
File ui/wm/core/capture_controller.cc (right):

https://codereview.chromium.org/780273003/diff/90001/ui/wm/core/capture_contr...
ui/wm/core/capture_controller.cc:65: it != delegates.end(); ++it) {
Consider using const auto&

[pkotwicz, 2014-12-16 18:04:02]

The CQ bit was checked by pkotwicz@chromium.org

[pkotwicz, 2014-12-16 18:04:05]

The CQ bit was unchecked by pkotwicz@chromium.org

[pkotwicz, 2014-12-16 18:04:09]

https://codereview.chromium.org/780273003/diff/90001/ui/wm/core/capture_contr...
File ui/wm/core/capture_controller.cc (right):

https://codereview.chromium.org/780273003/diff/90001/ui/wm/core/capture_contr...
ui/wm/core/capture_controller.cc:65: it != delegates.end(); ++it) {
Much shorter with const auto&

[pkotwicz, 2014-12-16 18:04:12]

The CQ bit was checked by pkotwicz@chromium.org

[commit-bot: I haz the power, 2014-12-16 18:04:59]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/780273003/110001

[commit-bot: I haz the power, 2014-12-16 20:03:10]

Committed patchset #3 (id:110001)

[commit-bot: I haz the power, 2014-12-16 20:04:12]

Patchset 3 (id:??) landed as
https://crrev.com/2865fb61212f41f2f1f605a018e6a8d3e53e6100
Cr-Commit-Position: refs/heads/master@{#308649}