mus/views: Create a mus OSExchangeData::Provider stub, and use it.

ui/views/mus/window_manager_connection.h

 // Copyright 2015 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.
 
 #ifndef UI_VIEWS_MUS_WINDOW_MANAGER_CONNECTION_H_
 #define UI_VIEWS_MUS_WINDOW_MANAGER_CONNECTION_H_
 
 #include <stdint.h>
 
 #include <map>
 #include <memory>
 #include <string>
 #include <vector>
 
 #include "base/macros.h"
 #include "base/observer_list.h"
 #include "services/shell/public/cpp/identity.h"
 #include "services/ui/public/cpp/window_tree_client_delegate.h"
+#include "ui/base/dragdrop/os_exchange_data_provider_factory.h"
 #include "ui/views/mus/mus_export.h"
 #include "ui/views/mus/screen_mus_delegate.h"
 #include "ui/views/widget/widget.h"
 
 namespace shell {
 class Connector;
 }
 
 namespace ui {
 class GpuService;
@@ skipping 13 matching lines @@
 // . Provides a Screen implementation backed by mus.
 // . Provides a Clipboard implementation backed by mus.
 // . Creates and owns a WindowTreeClient.
 // . Registers itself as the factory for creating NativeWidgets so that a
 //   NativeWidgetMus is created.
 // WindowManagerConnection is a singleton and should be created early on.
 //
 // TODO(sky): this name is now totally confusing. Come up with a better one.
 class VIEWS_MUS_EXPORT WindowManagerConnection
     : public NON_EXPORTED_BASE(ui::WindowTreeClientDelegate),
-      public ScreenMusDelegate {
+      public ScreenMusDelegate,
+      public ui::OSExchangeDataProviderFactory::Factory {
  public:
   ~WindowManagerConnection() override;
 
   static std::unique_ptr<WindowManagerConnection> Create(
       shell::Connector* connector,
       const shell::Identity& identity);
   static WindowManagerConnection* Get();
   static bool Exists();
 
   shell::Connector* connector() { return connector_; }
@@ skipping 26 matching lines @@
 
   // ui::WindowTreeClientDelegate:
   void OnEmbed(ui::Window* root) override;
   void OnDidDestroyClient(ui::WindowTreeClient* client) override;
   void OnEventObserved(const ui::Event& event, ui::Window* target) override;
 
   // ScreenMusDelegate:
   void OnWindowManagerFrameValuesChanged() override;
   gfx::Point GetCursorScreenPoint() override;
 
+  // ui:OSExchangeDataProviderFactory::Factory:
+  std::unique_ptr<OSExchangeData::Provider> BuildProvider() override;
+
   shell::Connector* connector_;
   shell::Identity identity_;
   std::unique_ptr<ScreenMus> screen_;
   std::unique_ptr<ui::WindowTreeClient> client_;
   std::unique_ptr<ui::GpuService> gpu_service_;
   // Must be empty on destruction.
   base::ObserverList<PointerWatcher, true> pointer_watchers_;
   base::ObserverList<TouchEventWatcher, true> touch_event_watchers_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowManagerConnection);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_MUS_WINDOW_MANAGER_CONNECTION_H_