mus: Implement interwindow drag and drop

services/ui/public/cpp/window.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/public/cpp/window.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <set>
@@ skipping 429 matching lines @@
 
 bool Window::HasFocus() const {
   return client_ && client_->GetFocusedWindow() == this;
 }
 
 void Window::SetCanFocus(bool can_focus) {
   if (client_)
     client_->SetCanFocus(server_id_, can_focus);
 }
 
+void Window::SetCanAcceptDrops(WindowDropTarget* drop_target) {
+  if (drop_target_ == drop_target)
+    return;
+  drop_target_ = drop_target;
+  if (client_)
+    client_->SetCanAcceptDrops(server_id_, !!drop_target_);
+}
+
 void Window::SetCanAcceptEvents(bool can_accept_events) {
   if (can_accept_events_ == can_accept_events)
     return;
   can_accept_events_ = can_accept_events;
   if (client_)
     client_->SetCanAcceptEvents(server_id_, can_accept_events_);
 }
 
 void Window::Embed(ui::mojom::WindowTreeClientPtr client, uint32_t flags) {
   Embed(std::move(client), base::Bind(&EmptyEmbedCallback), flags);
 }
 
 void Window::Embed(ui::mojom::WindowTreeClientPtr client,
                    const EmbedCallback& callback,
                    uint32_t flags) {
   if (PrepareForEmbed())
     client_->Embed(server_id_, std::move(client), flags, callback);
   else
     callback.Run(false);
 }
 
 void Window::RequestClose() {
   if (client_)
     client_->RequestClose(this);
 }
 
+void Window::PerformDragDrop(
+    int drag_pointer,
+    const std::map<std::string, std::vector<uint8_t>>& drag_data,
+    int drag_operation,
+    const gfx::Point& cursor_location,
+    const SkBitmap& bitmap,
+    const base::Callback<void(bool)>& callback) {
+  client_->PerformDragDrop(this, drag_pointer, drag_data, drag_operation,
+                           cursor_location, bitmap, callback);
+}
+
 void Window::PerformWindowMove(mojom::MoveLoopSource source,
                                const gfx::Point& cursor_location,
                                const base::Callback<void(bool)>& callback) {
   client_->PerformWindowMove(this, source, cursor_location, callback);
 }
 
 void Window::CancelWindowMove() {
   client_->CancelWindowMove(this);
 }
 
@@ skipping 416 matching lines @@
     notifier->NotifyWindowReordered();
 
   return true;
 }
 
 // static
 Window** Window::GetStackingTarget(Window* window) {
   return &window->stacking_target_;
 }
 }  // namespace ui