Integrate About page into Settings for Chrome OS settings in a window.

chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc

Index: chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
diff --git a/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc b/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
index 2c8ec46a6271fc15bdb5b4eda2bbab7e9a2f7524..b4acde4a309c4fe289404975b988658dac5d0de6 100644
--- a/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
+++ b/chrome/browser/ui/webui/chrome_web_ui_controller_factory.cc
@@ -390,8 +390,13 @@ WebUIFactoryFunction GetWebUIFactoryFunction(WebUI* web_ui,
   if (url.host() == chrome::kChromeUIQuotaInternalsHost)
     return &NewWebUI<QuotaInternalsUI>;
   // Settings are implemented with native UI elements on Android.
-  if (url.host() == chrome::kChromeUISettingsFrameHost)
+  // Handle chrome://settings if settings in a window and about in settings
+  // are enabled.
+  if (url.host() == chrome::kChromeUISettingsFrameHost ||
+      (url.host() == chrome::kChromeUISettingsHost &&
+       ::switches::AboutInSettingsEnabled())) {
     return &NewWebUI<options::OptionsUI>;
+  }
   if (url.host() == chrome::kChromeUISuggestionsInternalsHost)
     return &NewWebUI<SuggestionsInternalsUI>;
   if (url.host() == chrome::kChromeUISyncFileSystemInternalsHost)