Wires up drags to pointer watcher adapter.

ash/aura/pointer_watcher_adapter.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 "ash/aura/pointer_watcher_adapter.h"
 
 #include "ash/shell.h"
 #include "ui/aura/client/screen_position_client.h"
 #include "ui/aura/window.h"
 #include "ui/events/event.h"
 #include "ui/events/event_constants.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/views/pointer_watcher.h"
 #include "ui/views/widget/widget.h"
 
 namespace ash {
 
 PointerWatcherAdapter::PointerWatcherAdapter() {
   Shell::GetInstance()->AddPreTargetHandler(this);
 }
 
 PointerWatcherAdapter::~PointerWatcherAdapter() {
   Shell::GetInstance()->RemovePreTargetHandler(this);
 }
 
 void PointerWatcherAdapter::AddPointerWatcher(views::PointerWatcher* watcher,
-                                              bool wants_moves) {
+                                              views::RequestedEvents events) {
   // We only allow a watcher to be added once. That is, we don't consider
-  // the pair of |watcher| and |wants_move| unique, just |watcher|.
-  if (wants_moves) {
+  // the pair of |watcher| and |wants_move| and |wants_drags| unique, just
+  // |watcher|.
+  if (events == views::RequestedEvents::DRAGS) {
+    DCHECK(!move_watchers_.HasObserver(watcher));

[sky, 2016/08/26 15:36:54]

I think it's ok to assume a watcher isn't added more than once to any list. How
about moving all the DCHECKs outside the conditional.

[sammiequon, 2016/08/26 18:34:20]

Done.

+    DCHECK(!non_move_watchers_.HasObserver(watcher));
+    drag_watchers_.AddObserver(watcher);
+  } else if (events == views::RequestedEvents::MOVES) {
+    DCHECK(!drag_watchers_.HasObserver(watcher));
     DCHECK(!non_move_watchers_.HasObserver(watcher));
     move_watchers_.AddObserver(watcher);
   } else {
+    DCHECK(!drag_watchers_.HasObserver(watcher));
     DCHECK(!move_watchers_.HasObserver(watcher));
     non_move_watchers_.AddObserver(watcher);
   }
 }
 
 void PointerWatcherAdapter::RemovePointerWatcher(
     views::PointerWatcher* watcher) {
   non_move_watchers_.RemoveObserver(watcher);
   move_watchers_.RemoveObserver(watcher);
+  drag_watchers_.RemoveObserver(watcher);
 }
 
 void PointerWatcherAdapter::OnMouseEvent(ui::MouseEvent* event) {
   if (event->type() == ui::ET_MOUSE_CAPTURE_CHANGED) {
     FOR_EACH_OBSERVER(views::PointerWatcher, non_move_watchers_,
                       OnMouseCaptureChanged());
     FOR_EACH_OBSERVER(views::PointerWatcher, move_watchers_,
                       OnMouseCaptureChanged());
+    FOR_EACH_OBSERVER(views::PointerWatcher, drag_watchers_,
+                      OnMouseCaptureChanged());
     return;
   }
 
-  // For compatibility with the mus version, don't send drags.
+  // The mus version does not send drags.
   if (event->type() != ui::ET_MOUSE_PRESSED &&
       event->type() != ui::ET_MOUSE_RELEASED &&
-      event->type() != ui::ET_MOUSE_MOVED)
+      event->type() != ui::ET_MOUSE_MOVED &&
+      event->type() != ui::ET_MOUSE_DRAGGED)
     return;
 
   DCHECK(ui::PointerEvent::CanConvertFrom(*event));
   NotifyWatchers(ui::PointerEvent(*event), *event);
 }
 
 void PointerWatcherAdapter::OnTouchEvent(ui::TouchEvent* event) {
   // For compatibility with the mus version, don't send drags.
   if (event->type() != ui::ET_TOUCH_PRESSED &&
-      event->type() != ui::ET_TOUCH_RELEASED)
+      event->type() != ui::ET_TOUCH_RELEASED &&
+      event->type() != ui::ET_TOUCH_MOVED)
     return;
 
   DCHECK(ui::PointerEvent::CanConvertFrom(*event));
   NotifyWatchers(ui::PointerEvent(*event), *event);
 }
 
 gfx::Point PointerWatcherAdapter::GetLocationInScreen(
     const ui::LocatedEvent& event) const {
   aura::Window* target = static_cast<aura::Window*>(event.target());
   gfx::Point location_in_screen = event.location();
   aura::client::GetScreenPositionClient(target->GetRootWindow())
       ->ConvertPointToScreen(target, &location_in_screen);
   return location_in_screen;
 }
 
 views::Widget* PointerWatcherAdapter::GetTargetWidget(
     const ui::LocatedEvent& event) const {
   aura::Window* window = static_cast<aura::Window*>(event.target());
   return views::Widget::GetTopLevelWidgetForNativeView(window);
 }
 
 void PointerWatcherAdapter::NotifyWatchers(
     const ui::PointerEvent& event,
     const ui::LocatedEvent& original_event) {
   const gfx::Point screen_location(GetLocationInScreen(original_event));
   views::Widget* target_widget = GetTargetWidget(original_event);
   FOR_EACH_OBSERVER(
-      views::PointerWatcher, move_watchers_,
+      views::PointerWatcher, drag_watchers_,
       OnPointerEventObserved(event, screen_location, target_widget));
-  if (event.type() != ui::ET_POINTER_MOVED) {
+  if (original_event.type() != ui::ET_TOUCH_MOVED &&
+      original_event.type() != ui::ET_MOUSE_DRAGGED) {
+    FOR_EACH_OBSERVER(
+        views::PointerWatcher, move_watchers_,
+        OnPointerEventObserved(event, screen_location, target_widget));
+  }
+  if (event.type() != ui::ET_POINTER_MOVED &&
+      original_event.type() != ui::ET_MOUSE_DRAGGED) {
     FOR_EACH_OBSERVER(
         views::PointerWatcher, non_move_watchers_,
         OnPointerEventObserved(event, screen_location, target_widget));
   }
 }
 
 }  // namespace ash