Update ui::PointerEvent to support mouse wheel and capture change events.

ui/views/mus/pointer_watcher_event_router.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/views/mus/pointer_watcher_event_router.h"
 
 #include "services/ui/public/cpp/window.h"
 #include "services/ui/public/cpp/window_tree_client.h"
+#include "ui/display/screen.h"
 #include "ui/events/base_event_utils.h"
 #include "ui/events/event.h"
 #include "ui/views/mus/native_widget_mus.h"
 #include "ui/views/pointer_watcher.h"
 
 namespace views {
 
 PointerWatcherEventRouter::PointerWatcherEventRouter(
     ui::WindowTreeClient* client)
     : window_tree_client_(client) {
@@ skipping 59 matching lines @@
   // Check to see if we really have any observers left. This doesn't use
   // base::ObserverList<>::might_have_observers() because that returns true
   // during iteration over the list even when the last observer is removed.
   base::ObserverList<PointerWatcher>::Iterator iterator(&pointer_watchers_);
   return !!iterator.GetNext();
 }
 
 void PointerWatcherEventRouter::OnWindowTreeCaptureChanged(
     ui::Window* gained_capture,
     ui::Window* lost_capture) {
-  FOR_EACH_OBSERVER(PointerWatcher, pointer_watchers_, OnMouseCaptureChanged());
+  const ui::MouseEvent mouse_event(ui::ET_MOUSE_CAPTURE_CHANGED, gfx::Point(),
+                                   gfx::Point(), ui::EventTimeForNow(), 0, 0);
+  const ui::PointerEvent event(mouse_event);
+  FOR_EACH_OBSERVER(PointerWatcher, pointer_watchers_,
+                    OnPointerEventObserved(event, gfx::Point(), nullptr));
 }
 
 void PointerWatcherEventRouter::OnDidDestroyClient(
     ui::WindowTreeClient* client) {
   DCHECK(!pointer_watchers_.might_have_observers());
   DCHECK_EQ(client, window_tree_client_);
   window_tree_client_->RemoveObserver(this);
   window_tree_client_ = nullptr;
 }
 
 }  // namespace views