Add EventTargeterDelegate for EventTargeter in mus-ws.

services/ui/ws/event_targeter_delegate.h

Index: services/ui/ws/event_targeter_delegate.h
diff --git a/services/ui/ws/event_targeter_delegate.h b/services/ui/ws/event_targeter_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..2e46860090028b3f5a8e6ee0645e716bc256406a
--- /dev/null
+++ b/services/ui/ws/event_targeter_delegate.h
@@ -0,0 +1,33 @@
+// Copyright 2017 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_UI_WS_EVENT_TARGETER_DELEGATE_H_
+#define SERVICES_UI_WS_EVENT_TARGETER_DELEGATE_H_
+
+#include <stdint.h>
+
+namespace gfx {
+class Point;
+}
+
+namespace ui {
+namespace ws {
+class ServerWindow;
+
+// Used by EventTargeter to talk to WindowManagerState.
+class EventTargeterDelegate {
+ public:
+  // Calls EventDispatcherDelegate::GetRootWindowContaining, see
+  // event_dispatcher_delegate.h for details.
+  virtual ServerWindow* GetRootWindowContaining(gfx::Point* location_in_display,
+                                                int64_t* display_id) = 0;
+
+ protected:
+  virtual ~EventTargeterDelegate() {}
+};
+
+}  // namespace ws
+}  // namespace ui
+
+#endif  // SERVICES_UI_WS_EVENT_TARGETER_DELEGATE_H_