Stop foreground depending on background in gyp v2

ui/file_manager/externs/background/progress_center.js

Index: ui/file_manager/externs/background/progress_center.js
diff --git a/ui/file_manager/externs/background/progress_center.js b/ui/file_manager/externs/background/progress_center.js
new file mode 100644
index 0000000000000000000000000000000000000000..ac689d3857f910b34c3b8d7d2f3c6e029ec16dcc
--- /dev/null
+++ b/ui/file_manager/externs/background/progress_center.js
@@ -0,0 +1,44 @@
+// 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.
+
+/**
+ * Progress center at the background page.
+ * @constructor
+ * @struct
+ */
+var ProgressCenter = function() {};
+
+/**
+ * Updates the item in the progress center.
+ * If the item has a new ID, the item is added to the item list.
+ *
+ * @param {ProgressCenterItem} item Updated item.
+ */
+ProgressCenter.prototype.updateItem = function(item) {};
+
+/**
+ * Requests to cancel the progress item.
+ * @param {string} id Progress ID to be requested to cancel.
+ */
+ProgressCenter.prototype.requestCancel = function(id) {};
+
+/**
+ * Adds a panel UI to the notification center.
+ * @param {ProgressCenterPanel} panel Panel UI.
+ */
+ProgressCenter.prototype.addPanel = function(panel) {};
+
+/**
+ * Removes a panel UI from the notification center.
+ * @param {ProgressCenterPanel} panel Panel UI.
+ */
+ProgressCenter.prototype.removePanel = function(panel) {};
+
+/**
+ * Obtains item by ID.
+ * @param {string} id ID of progress item.
+ * @return {ProgressCenterItem} Progress center item having the specified
+ *     ID. Null if the item is not found.
+ */
+ProgressCenter.prototype.getItemById = function(id) {};