Revert of Compile more targets in foreground/js/ui in gyp v2 (3)

ui/file_manager/externs/drag_target.js

-// 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.
-
-/**
- * @interface
- */
-function DragTarget(){};
-
-/**
- * This definition is required to satisfy
- * ui/file_manager/file_manager/foreground/js/ui/drag_selector.js.
- *
- * @param {number} x
- * @param {number} y
- * @param {number=} opt_width
- * @param {number=} opt_height
- * @return {Array<number>}
- */
-DragTarget.prototype.getHitElements = function(x, y, opt_width, opt_height) {};