I'll poke at this to see if we are at least trying to set the pointer.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/adb99b98e9271ed418fbc941852f5547b0d5d59c

commit adb99b98e9271ed418fbc941852f5547b0d5d59c
Author: sky <sky@chromium.org>
Date: Tue Feb 07 19:22:22 2017

Fixes bugs in cursor handling

. CURSOR_NULL on ozone seems to mean leave the last cursor. So, this
  change makes sure we use POINTER rather than CURSOR_NULL.
. aura sets the cursor on the root window, which means mus needs to
  pick up the cursor from the root. I'm not particularly thrilled
  about this, but changing mus is a lot more straightforward than
  changing aura.

BUG= 689126 
TEST=covered by tests
R=erg@chromium.org

Review-Url: https://codereview.chromium.org/2680883002
Cr-Commit-Position: refs/heads/master@{#448690}

[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/cursor_unittest.cc
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/event_dispatcher.cc
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/event_dispatcher.h
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/event_dispatcher_delegate.h
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/server_window.cc
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/test_utils.cc
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/test_utils.h
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/window_manager_state_unittest.cc
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/window_server.cc
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/window_server.h
[modify] https://crrev.com/adb99b98e9271ed418fbc941852f5547b0d5d59c/services/ui/ws/window_tree_unittest.cc