Start to decouple display::Display from ws::PlatformDisplay.

services/ui/ws/window_tree.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 "services/ui/ws/window_tree.h"
 
 #include <stddef.h>
 
 #include <utility>
 
@@ skipping 179 matching lines @@
 }
 
 void WindowTree::AddRootForWindowManager(const ServerWindow* root) {
   DCHECK(window_manager_internal_);
   const ClientWindowId client_window_id(WindowIdToTransportId(root->id()));
   DCHECK_EQ(0u, client_id_to_window_id_map_.count(client_window_id));
   client_id_to_window_id_map_[client_window_id] = root->id();
   window_id_to_client_id_map_[root->id()] = client_window_id;
   roots_.insert(root);
 
-  Display* display = GetDisplay(root);
-  DCHECK(display);
+  Display* ws_display = GetDisplay(root);
+  DCHECK(ws_display);
 
-  window_manager_internal_->WmNewDisplayAdded(display->ToDisplay(),
+  window_manager_internal_->WmNewDisplayAdded(ws_display->GetDisplay(),
                                               WindowToWindowData(root),
                                               root->parent()->IsDrawn());
 }
 
 void WindowTree::OnWindowDestroyingTreeImpl(WindowTree* tree) {
   if (event_source_wms_ && event_source_wms_->window_tree() == tree)
     event_source_wms_ = nullptr;
 
   // Notify our client if |tree| was embedded in any of our windows.
   for (const auto* tree_root : tree->roots_) {
@@ skipping 1965 matching lines @@
   client()->OnCompleteDrop(client_window_id.id, event_flags, cursor_offset,
                            effect_bitmask, callback);
 }
 
 void WindowTree::PerformOnDragDropDone() {
   client()->OnDragDropDone();
 }
 
 }  // namespace ws
 }  // namespace ui