mus: Keep track of the drag cursor during DnD operations.

services/ui/ws/event_dispatcher.cc

Index: services/ui/ws/event_dispatcher.cc
diff --git a/services/ui/ws/event_dispatcher.cc b/services/ui/ws/event_dispatcher.cc
index fb554ee13af9bfd85138d69f8f0cd8ed26992040..7a6ec0a226e5786a41202224ed6430186ac89497 100644
--- a/services/ui/ws/event_dispatcher.cc
+++ b/services/ui/ws/event_dispatcher.cc
@@ -104,6 +104,11 @@ void EventDispatcher::SetMousePointerScreenLocation(
 }
 
 bool EventDispatcher::GetCurrentMouseCursor(int32_t* cursor_out) {
+  if (drag_controller_) {
+    *cursor_out = drag_controller_->current_cursor();
+    return true;
+  }
+
   if (!mouse_cursor_source_window_)
     return false;
 
@@ -172,7 +177,7 @@ void EventDispatcher::SetDragDropSourceWindow(
     uint32_t drag_operations) {
   CancelImplicitCaptureExcept(nullptr);
   drag_controller_ = base::MakeUnique<DragController>(
-      drag_source, window, source_connection, drag_pointer,
+      this, drag_source, window, source_connection, drag_pointer,
       std::move(mime_data), drag_operations);
 }
 
@@ -612,5 +617,9 @@ void EventDispatcher::OnWindowDestroyed(ServerWindow* window) {
     mouse_cursor_source_window_ = nullptr;
 }
 
+void EventDispatcher::OnDragCursorUpdated() {
+  delegate_->UpdateNativeCursorFromDispatcher();
+}
+
 }  // namespace ws
 }  // namespace ui