[MD settings] appearance theme and wallpaper

chrome/browser/resources/settings/appearance_page/appearance_browser_proxy.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.
+
+cr.define('settings', function() {
+  /** @interface */
+  function AppearanceBrowserProxy() {}
+
+  AppearanceBrowserProxy.prototype = {
+    /**
+     * @return {!Promise<boolean>} Whether the theme may be reset.
+     */
+    getResetThemeEnabled: assertNotReached,
+
+<if expr="chromeos">
+    /**
+     * ChromeOS only.

[dpapad, 2016/04/20 01:16:58]

Nit(optional): You can remove the comment now, since it is redundant.

[dschuyler, 2016/04/20 19:15:45]

Done.

+     */
+    openWallpaperManager: assertNotReached,
+</if>
+
+    resetTheme: assertNotReached,
+  };
+
+  /**
+   * @implements {settings.AppearanceBrowserProxy}
+   * @constructor
+   */
+  function AppearanceBrowserProxyImpl() {}
+
+  cr.addSingletonGetter(AppearanceBrowserProxyImpl);
+
+  AppearanceBrowserProxyImpl.prototype = {
+    /** @override */
+    getResetThemeEnabled: function() {
+      return cr.sendWithPromise('getResetThemeEnabled');
+    },
+
+<if expr="chromeos">
+    /** @override */
+    openWallpaperManager: function() {
+      chrome.send('openWallpaperManager');
+    },
+
+    /** @override */
+    resetTheme: function() {
+      chrome.send('resetTheme');
+    },
+</if>
+  };
+
+  return {
+    AppearanceBrowserProxy: AppearanceBrowserProxy,
+    AppearanceBrowserProxyImpl: AppearanceBrowserProxyImpl,
+  };
+});