[Ozone-Drm] Notify cursor of channel established last

ui/ozone/platform/drm/host/drm_cursor.cc

 // Copyright 2014 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/ozone/platform/drm/host/drm_cursor.h"
 
 #include "base/thread_task_runner_handle.h"
 #include "ui/base/cursor/ozone/bitmap_cursor_factory_ozone.h"
 #include "ui/gfx/geometry/point.h"
 #include "ui/gfx/geometry/point_conversions.h"
 #include "ui/gfx/geometry/point_f.h"
 #include "ui/ozone/common/gpu/ozone_gpu_messages.h"
-#include "ui/ozone/platform/drm/host/drm_gpu_platform_support_host.h"
 #include "ui/ozone/platform/drm/host/drm_window_host.h"
 #include "ui/ozone/platform/drm/host/drm_window_host_manager.h"
 
 #if defined(OS_CHROMEOS)
 #include "ui/events/ozone/chromeos/cursor_controller.h"
 #endif
 
 namespace ui {
 
-DrmCursor::DrmCursor(DrmWindowHostManager* window_manager,
-                     DrmGpuPlatformSupportHost* gpu_platform_support_host)
-    : window_manager_(window_manager),
-      gpu_platform_support_host_(gpu_platform_support_host) {
+DrmCursor::DrmCursor(DrmWindowHostManager* window_manager)
+    : window_manager_(window_manager) {
 }
 
 DrmCursor::~DrmCursor() {
-  gpu_platform_support_host_->UnregisterHandler(this);
-}
-
-void DrmCursor::Init() {
-  gpu_platform_support_host_->RegisterHandler(this);
 }
 
 void DrmCursor::SetCursor(gfx::AcceleratedWidget window,
                           PlatformCursor platform_cursor) {
   DCHECK(ui_task_runner_->BelongsToCurrentThread());
   DCHECK_NE(window, gfx::kNullAcceleratedWidget);
 
   scoped_refptr<BitmapCursorOzone> bitmap =
       BitmapCursorFactoryOzone::GetBitmapCursor(platform_cursor);
 
@@ skipping 250 matching lines @@
 }
 
 DrmCursor::CursorState::CursorState()
     : window(gfx::kNullAcceleratedWidget), host_id(-1) {
 }
 
 DrmCursor::CursorState::~CursorState() {
 }
 
 }  // namespace ui