Eliminate WindowTreeConnection

components/mus/public/cpp/window_tree_delegate.h

-// 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.
-
-#ifndef COMPONENTS_MUS_PUBLIC_CPP_WINDOW_TREE_DELEGATE_H_
-#define COMPONENTS_MUS_PUBLIC_CPP_WINDOW_TREE_DELEGATE_H_
-
-#include <string>
-
-#include "components/mus/public/interfaces/window_tree.mojom.h"
-#include "services/shell/public/interfaces/interface_provider.mojom.h"
-
-namespace ui {
-class Event;
-}
-
-namespace mus {
-
-class Window;
-class WindowTreeConnection;
-
-// Interface implemented by an application using the window manager.
-//
-// WindowTreeConnection is deleted by any of the following:
-// . If all the roots of the connection are destroyed and the connection is
-//   configured to delete when there are no roots (the default). This happens
-//   if the owner of the roots Embed()s another app in all the roots, or all
-//   the roots are explicitly deleted.
-// . The connection to the window manager is lost.
-// . Explicitly by way of calling delete.
-//
-// When the WindowTreeConnection is deleted all windows are deleted (and
-// observers notified). This is followed by notifying the delegate by way of
-// OnConnectionLost().
-class WindowTreeDelegate {
- public:
-  // Called when the application implementing this interface is embedded at
-  // |root|.
-  // NOTE: this is only invoked if the WindowTreeConnection is created with
-  // an InterfaceRequest.
-  virtual void OnEmbed(Window* root) = 0;
-
-  // Sent when another app is embedded in |root| (one of the roots of the
-  // connection). Afer this call |root| is deleted. If |root| is the only root
-  // and the connection is configured to delete when there are no roots (the
-  // default), then after |root| is destroyed the connection is destroyed as
-  // well.
-  virtual void OnUnembed(Window* root);
-
-  // Called from the destructor of WindowTreeConnection after all the Windows
-  // have been destroyed. |connection| is no longer valid after this call.
-  virtual void OnConnectionLost(WindowTreeConnection* connection) = 0;
-
-  // Called when the WindowTreeConnection receives an input event observed via
-  // SetEventObserver(). |target| may be null for events that were sent to
-  // windows owned by other processes.
-  virtual void OnEventObserved(const ui::Event& event, Window* target) = 0;
-
- protected:
-  virtual ~WindowTreeDelegate() {}
-};
-
-}  // namespace mus
-
-#endif  // COMPONENTS_MUS_PUBLIC_CPP_WINDOW_TREE_DELEGATE_H_