Launch webstore widget app when unsupported printer is plugged in

components/chrome_apps/webstore_widget/externs/chrome_webstore_widget_private.js

Index: components/chrome_apps/webstore_widget/externs/chrome_webstore_widget_private.js
diff --git a/components/chrome_apps/webstore_widget/externs/chrome_webstore_widget_private.js b/components/chrome_apps/webstore_widget/externs/chrome_webstore_widget_private.js
new file mode 100644
index 0000000000000000000000000000000000000000..4dc9ee40c192e0ba89257bfc81884ecff1e89d53
--- /dev/null
+++ b/components/chrome_apps/webstore_widget/externs/chrome_webstore_widget_private.js
@@ -0,0 +1,78 @@
+// Copyright 2015 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.
+
+/** @const */
+chrome.webstoreWidgetPrivate = {};
+
+/**
+ * @enum {string}
+ */
+chrome.webstoreWidgetPrivate.Type = {
+  PRINTER_PROVIDER: 'PRINTER_PROVIDER'
+};
+
+/**
+ * @typedef {{vendorId: number, productId: number}}
+ */
+chrome.webstoreWidgetPrivate.UsbId;
+
+/**
+ * @typedef {{
+ *   options: chrome.webstoreWidgetPrivate.Type,
+ *   usbId: (chrome.webstoreWidgetPrivate.UsbId|undefined)
+ * }}
+ */
+chrome.webstoreWidgetPrivate.Options;
+
+/**
+ * @constructor
+ */
+chrome.webstoreWidgetPrivate.ShowWidgetEvent;
+
+/**
+ * @param {function(!chrome.webstoreWidgetPrivate.Options)} callback
+ */
+chrome.webstoreWidgetPrivate.ShowWidgetEvent.prototype.addListener = function(
+    callback) {
+};
+
+/**
+ * @param {function(!chrome.webstoreWidgetPrivate.Options)} callback
+ */
+chrome.webstoreWidgetPrivate.ShowWidgetEvent.prototype.removeListener =
+    function(callback) {};
+
+/**
+ * @param {function(!chrome.webstoreWidgetPrivate.Options)} callback
+ * @return {boolean}
+ */
+chrome.webstoreWidgetPrivate.ShowWidgetEvent.prototype.hasListener = function(
+    callback) {
+};
+
+/**
+ * @return {boolean}
+ */
+chrome.webstoreWidgetPrivate.ShowWidgetEvent.prototype.hasListeners =
+    function() {};
+
+/**
+ * @typedef {!chrome.webstoreWidgetPrivate.ShowWidgetEvent}
+ */
+chrome.webstoreWidgetPrivate.onShowWidget;
+
+/**
+ * @param {function(Object.<string, string>)} callback
+ */
+chrome.webstoreWidgetPrivate.getStrings = function(callback) {};
+
+/**
+ * Installs the app with ID {@code itemId}.
+ * @param {string} itemId
+ * @param {boolean} silentInstall
+ * @param {function()} callback
+ */
+chrome.webstoreWidgetPrivate.installWebstoreItem = function(
+    itemId, silentInstall, callback) {
+};