Remove controller concept from the ARC support extension.

chrome/browser/resources/chromeos/arc_support/background.js

 // Copyright 2016 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.
 
 /**
  * UI Pages. Note the order must be in sync with the ArcAuthService::UIPage
  * enum.
  * @type {Array<string>}
  */
 var UI_PAGES = ['none',
@@ skipping 61 matching lines @@
 
 /**
  * Host window inner default height.
  * @const {number}
  */
 var INNER_HEIGHT = 688;
 
 
 /**
  * Sends a native message to ArcSupportHost.
- * @param {string} code The action code in message.
- * @param {Object=} opt_Props Extra properties for the message.
+ * @param {string} event The event type in message.
+ * @param {Object=} opt_props Extra properties for the message.
  */
-function sendNativeMessage(code, opt_Props) {
-  var message = Object.assign({'action': code}, opt_Props);
+function sendNativeMessage(event, opt_props) {
+  var message = Object.assign({'event': event}, opt_props);
   port.postMessage(message);
 }
 
 /**
  * Helper function that sets inner content for an option which includes text,
  * link to 'learn more' section. This also creates an indicator showing that
  * option is controlled by policy and inserts it before link element.
  * @param {string} textId Id of the label element to process.
  * @param {string} learnMoreLinkId Id inner link to 'learn more' element.
  * @param {string} indicatorId Id of indicator to create.
@@ skipping 365 matching lines @@
         // it safe to make it up to window width.
         lsoView.style.width = '100%';
         return;
       }
 
       lsoView.executeScript({code: 'document.title;'}, function(results) {
         var authCodePrefix = 'Success code=';
         if (results && results.length == 1 && typeof results[0] == 'string' &&
             results[0].substring(0, authCodePrefix.length) == authCodePrefix) {
           var authCode = results[0].substring(authCodePrefix.length);
-          sendNativeMessage('setAuthCode', {code: authCode});
+          sendNativeMessage('onAuthSucceeded', {'code': authCode});

[Luis Héctor Chávez, 2016/10/03 20:40:16]

Google's JavaScript style guide indicate that object literals should not have
quotes, unless needed to disambiguate syntax:
https://google.github.io/styleguide/javascriptguide.xml?showone=Array_and_Obj...

I also found 4529 instances of non-quoted names vs. 483 instances of quoted
names in c/b/resources, so it seems to also be the convention.

[hidehiko, 2016/10/04 04:48:19]

Updated as you suggested.

         } else {
           setErrorMessage(appWindow.contentWindow.loadTimeData.getString(
               'authorizationFailed'));
           showPage('error');
         }
       });
     };
 
     var requestFilter = {
       urls: ['<all_urls>'],
@@ skipping 39 matching lines @@
     // webview is not allowed to open links in the new window. Hook these events
     // and open links in context of main page.
     termsView.addEventListener('newwindow', function(event) {
       event.preventDefault();
       chrome.browser.openTab({'url': event.targetUrl}, function() {});
     });
 
     var onAgree = function() {
       termsAccepted = true;
 
+      var data = {};
       var enableMetrics = doc.getElementById('enable-metrics');
       if (!enableMetrics.hidden) {
-        sendNativeMessage('enableMetrics', {
-          'enabled': enableMetrics.checked
-        });
+        data['isMetricsEnabled'] = enableMetrics.checked;

[Luis Héctor Chávez, 2016/10/03 20:40:16]

I'm not _entirely_ sure that this particular rule applies here:
https://google.github.io/styleguide/javascriptguide.xml?showone=Associative_A...

but in any case object.prop is more idiomatic and occurs 99k times vs. 1k times
for object['prop'].

And actually, you can construct this object upfront and be even more compliant
with the style guide:

var data = {
  isMetricsEnabled: !enableMedtrics.hidden && enableMetrics.checked,
  ....
};

[hidehiko, 2016/10/04 04:48:19]

Done.

       }
-
       var enableBackupRestore = doc.getElementById('enable-backup-restore');
-      sendNativeMessage('setBackupRestore', {
-        'enabled': enableBackupRestore.checked
-      });
+      data['isBackupRestoreEnabled'] = enableBackupRestore.checked;
 
       var enableLocationService = doc.getElementById('enable-location-service');
-      sendNativeMessage('setLocationService', {
-        'enabled': enableLocationService.checked
-      });
+      data['isLocationServiceEnabled'] = enableLocationService.checked;
 
-      sendNativeMessage('startLso');
+      sendNativeMessage('onAgreed', data);
     };
 
     var onCancel = function() {
       if (appWindow) {
         appWindow.close();
       }
     };
 
     var onRetry = function() {
       if (termsAccepted) {
-        sendNativeMessage('startLso');
+        // Reuse the onAgree() in case that the user has already accepted
+        // the ToS.
+        onAgree();
       } else {
         loadInitialTerms();
       }
     };
 
     var onSendFeedback = function() {
-      sendNativeMessage('sendFeedback');
+      sendNativeMessage('onSendFeedbackClicked');
     };
 
     doc.getElementById('button-agree').addEventListener('click', onAgree);
     doc.getElementById('button-cancel').addEventListener('click', onCancel);
     doc.getElementById('button-retry').addEventListener('click', onRetry);
     doc.getElementById('button-send-feedback')
         .addEventListener('click', onSendFeedback);
 
     connectPort();
   };
@@ skipping 27 matching lines @@
       type: 'chrome',
       color: '#ffffff'
     },
     'innerBounds': {
       'width': INNER_WIDTH,
       'height': INNER_HEIGHT
     }
   };
   chrome.app.window.create('main.html', options, onWindowCreated);
 });