cros: Allow user to configure note taking app in md-settings.

chrome/browser/resources/settings/device_page/device_page_browser_proxy.js

Index: chrome/browser/resources/settings/device_page/device_page_browser_proxy.js
diff --git a/chrome/browser/resources/settings/device_page/device_page_browser_proxy.js b/chrome/browser/resources/settings/device_page/device_page_browser_proxy.js
index 0f7ed4dbc8dfc6cc859e6ada503cfb3b4c3047db..049754587c9be7d4ad85f8fe902132da7139a62c 100644
--- a/chrome/browser/resources/settings/device_page/device_page_browser_proxy.js
+++ b/chrome/browser/resources/settings/device_page/device_page_browser_proxy.js
@@ -63,6 +63,27 @@ cr.define('settings', function() {
      *     battery (no external power source).
      */
     setPowerSource: function(powerSourceId) {},
+
+    /**
+     * |callback| is run when there is new note-taking app information
+     * available or after |requestNoteTakingApps| has been called.
+     * @param {function(Array<{name:string, value:string, preferred:boolean}>,
+     *     boolean):void} callback Callback to run.
+     */
+    onNoteTakingAppsUpdated: function(callback) {},
+
+    /**
+     * Request current note-taking app info. Invokes any callback registered in
+     * |onNoteTakingAppsUpdated|.
+     */
+    requestNoteTakingApps: function() {},
+
+    /**
+     * Changes the preferred note taking app.
+     * @param {string} appId The app id. This should be a value retrieved from a
+     *     |onNoteTakingAppsUpdated| callback.
+     */
+    setPreferredNoteTakingApp: function(appId) {},
   };
 
   /**
@@ -105,6 +126,21 @@ cr.define('settings', function() {
     setPowerSource: function(powerSourceId) {
       chrome.send('setPowerSource', [powerSourceId]);
     },
+
+    /** @override */
+    onNoteTakingAppsUpdated: function(callback) {
+      cr.addWebUIListener('onNoteTakingAppsUpdated', callback);
+    },

[stevenjb, 2017/01/25 01:40:08]

Hmm. I haven't seen this done as a proxy before. I would expect the usage to be
more like:

proxy_.addListener('onNoteTakingAppsUpdated', callback)

Or

proxy_.setNoteTakingAppsUpdatedCallback(callback)

[jdufault, 2017/02/03 21:32:08]

Done.

+
+    /** @override */
+    requestNoteTakingApps: function() {
+      chrome.send('requestNoteTakingApps');
+    },
+
+    /** @override */
+    setPreferredNoteTakingApp: function(appId) {
+      chrome.send('setPreferredNoteTakingApp', [appId]);
+    },
   };
 
   return {