Show an error dialog if Chrome Web Store widget fails to load

components/chrome_apps/webstore_widget/app/main.js

 // 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.
 
 //<include src="../../../../ui/webui/resources/js/cr.js">
 //<include src="../../../../ui/webui/resources/js/load_time_data.js">
 //<include src="../../../../ui/webui/resources/js/i18n_template_no_process.js">
 //<include src="../../../../ui/webui/resources/js/cr/event_target.js">
 //<include src="../../../../ui/webui/resources/js/cr/ui/dialogs.js">
 
@@ skipping 22 matching lines @@
 }
 
 /**
  * Default strings.
  */
 var defaultStrings = {
   'language': 'en',
   'LINK_TO_WEBSTORE': '[LOCALIZE ME] Learn more...',
   'INSTALLATION_FAILED_MESSAGE': '[LOCALIZE ME] Installation failed!',
   'OK_BUTTON': '[LOCALIZE ME] OK',
-  'TITLE_PRINTER_PROVIDERS': '[LOCALIZE ME] Select app for your printer'
+  'TITLE_PRINTER_PROVIDERS': '[LOCALIZE ME] Select app for your printer',
+  'DEFAULT_ERROR_MESSAGE': '[LOCALIZE ME] Failure'
 };
 
 /**
  * @param {string} id The string id.
  * @return {string}
  */
 function getString(id) {
   return loadTimeData.getString(id) || defaultStrings[id] || '';
 }
 
@@ skipping 60 matching lines @@
         }
         callback(token);
       });
     }
   };
 }
 
 function initializeTopbarButtons() {
   $('close-button').addEventListener('click', function(e) {
     e.preventDefault();
-    chrome.app.window.current().close();
+    closeAppWindow();
   });
 
   $('close-button').addEventListener('mousedown', function(e) {
     e.preventDefault();
   });
 
   $('minimize-button').addEventListener('click', function(e) {
     e.preventDefault();
     chrome.app.window.current().minimize();
   });
 
   $('minimize-button').addEventListener('mousedown', function(e) {
     e.preventDefault();
   });
 }
 
+/**
+ * @param {!CWSWidgetContainer.Result} result The result reported by the widget.
+ */
+function showWidgetResult(result) {
+  // TODO(tbarzic): Add some UI to show on success.
+  if (result != CWSWidgetContainer.Result.FAILED) {
+    closeAppWindow();
+    return;
+  }
+
+  var dialog = new CWSWidgetContainerErrorDialog($('widget-container-root'));
+  dialog.show(getString('DEFAULT_ERROR_MESSAGE'),
+              closeAppWindow,
+              closeAppWindow);
+}
+
+/** Closes the current app window. */
+function closeAppWindow() {
+  chrome.app.window.current().close();
+}
+
 window.addEventListener('DOMContentLoaded', function() {
   initializeTopbarButtons();
 
   chrome.webstoreWidgetPrivate.getStrings(function(strings) {
     loadTimeData.data = strings;
     i18nTemplate.process(document, loadTimeData);
 
     cr.ui.dialogs.BaseDialog.OK_LABEL = getString('OK_BUTTON');
 
     document.title = getString('TITLE_PRINTER_PROVIDERS');
@@ skipping 18 matching lines @@
         document, root, platformDelegate, {} /* state */);
 
     widgetContainer.ready()
         /** @return {!Promise.<CWSWidgetContainer.ResolveReason>} */
         .then(function() {
           return widgetContainer.start(window.params.filter,
                                        window.params.webstoreUrl);
         })
         /** @param {!CWSWidgetContainer.ResolveReason} reason */
         .then(function(reason) {
-          chrome.app.window.current().close();
+          if (reason != CWSWidgetContainer.ResolveReason.DONE)
+            return;
+
+          var result = widgetContainer.finalizeAndGetResult();
+          showWidgetResult(result.result);
         })
         /** @param {*} error */
         .catch(function(error) {
-          // TODO(tbarzic): Add error UI.
-          console.error(error);
+          showWidgetResult(CWSWidgetContainer.Result.FAILED);
         });
   });
 });
 })();