Move DropTargetEvent back to ui/base for the time being as it depends on OSExchangeData which I don…

ui/base/dragdrop/drop_target_event.h

Index: ui/base/dragdrop/drop_target_event.h
diff --git a/ui/base/dragdrop/drop_target_event.h b/ui/base/dragdrop/drop_target_event.h
new file mode 100644
index 0000000000000000000000000000000000000000..88fcfc11986ee2d2e8cace096391d43a7a8400e7
--- /dev/null
+++ b/ui/base/dragdrop/drop_target_event.h
@@ -0,0 +1,36 @@
+// Copyright (c) 2013 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_BASE_DRAGDROP_DROP_TARGET_EVENT_H_
+#define UI_BASE_DRAGDROP_DROP_TARGET_EVENT_H_
+
+#include "ui/events/event.h"
+#include "ui/base/dragdrop/os_exchange_data.h"
+
+namespace ui {
+
+class UI_EXPORT DropTargetEvent : public LocatedEvent {
+ public:
+  DropTargetEvent(const OSExchangeData& data,
+                  const gfx::Point& location,
+                  const gfx::Point& root_location,
+                  int source_operations);
+
+  const OSExchangeData& data() const { return data_; }
+  int source_operations() const { return source_operations_; }
+
+ private:
+  // Data associated with the drag/drop session.
+  const OSExchangeData& data_;
+
+  // Bitmask of supported DragDropTypes::DragOperation by the source.
+  int source_operations_;
+
+  DISALLOW_COPY_AND_ASSIGN(DropTargetEvent);
+};
+
+}  // namespace ui
+
+#endif  // UI_BASE_DRAGDROP_DROP_TARGET_EVENT_H_
+