Enable user change background image in settings page in Aura build.

chrome/browser/resources/options2/options.js

Index: chrome/browser/resources/options2/options.js
diff --git a/chrome/browser/resources/options2/options.js b/chrome/browser/resources/options2/options.js
index 55287dc2e6bb6d9f83dc34c7055d8cbc6914a8b8..d73b2a5809934c9ae7dec88eea3d6bdd2480e972 100644
--- a/chrome/browser/resources/options2/options.js
+++ b/chrome/browser/resources/options2/options.js
@@ -167,6 +167,13 @@ function load() {
                                   LanguageOptions.getInstance());
     }
   }
+
+  if (SetWallpaperOptions) {
+    OptionsPage.registerOverlay(SetWallpaperOptions.getInstance(),
+                                BrowserOptions.getInstance(),
+                                [$('set-wallpaper')]);
+  }
+
   if (!cr.isWindows && !cr.isMac) {
     OptionsPage.registerOverlay(CertificateBackupOverlay.getInstance(),
                                 CertificateManager.getInstance());