Revert "Delete the ViewManager and WindowManager services."

services/view_manager/server_view_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 SERVICES_VIEW_MANAGER_SERVER_VIEW_DELEGATE_H_
+#define SERVICES_VIEW_MANAGER_SERVER_VIEW_DELEGATE_H_
+
+#include "mojo/services/view_manager/interfaces/view_manager_constants.mojom.h"
+
+namespace gfx {
+class Rect;
+}
+
+namespace mojo {
+class ViewportMetrics;
+}
+
+namespace view_manager {
+
+class ServerView;
+
+// ServerViewDelegate is notified at key points in the lifetime of a
+// ServerView. Some of the functions are similar to that of
+// ServerViewObserver. For example, ServerViewDelegate::PrepareToDestroyView()
+// and ServerViewObserver::OnWillDestroyView(). The key difference between
+// the two are the ServerViewDelegate ones are always notified first, and
+// ServerViewDelegate gets non-const arguments.
+class ServerViewDelegate {
+ public:
+  // Invoked when a view is about to be destroyed; before any of the children
+  // have been removed and before the view has been removed from its parent.
+  virtual void PrepareToDestroyView(ServerView* view) = 0;
+
+  virtual void PrepareToChangeViewHierarchy(ServerView* view,
+                                            ServerView* new_parent,
+                                            ServerView* old_parent) = 0;
+
+  virtual void PrepareToChangeViewVisibility(ServerView* view) = 0;
+
+  virtual void OnScheduleViewPaint(const ServerView* view) = 0;
+
+ protected:
+  virtual ~ServerViewDelegate() {}
+};
+
+}  // namespace view_manager
+
+#endif  // SERVICES_VIEW_MANAGER_SERVER_VIEW_DELEGATE_H_