Add webui handler for promotions on Android NTP.

chrome/browser/prefs/browser_prefs.cc

Index: chrome/browser/prefs/browser_prefs.cc
diff --git a/chrome/browser/prefs/browser_prefs.cc b/chrome/browser/prefs/browser_prefs.cc
index 1e2a82484ceba19288be28bd5470e1970ccd2cb6..f750e51b449aad00c32a856a9c58c68ebed8604b 100644
--- a/chrome/browser/prefs/browser_prefs.cc
+++ b/chrome/browser/prefs/browser_prefs.cc
@@ -111,6 +111,10 @@
 #include "chrome/browser/chrome_to_mobile_service.h"
 #endif
 
+#if defined(OS_ANDROID)
+#include "chrome/browser/ui/webui/ntp/android/promo_handler.h"
+#endif
+
 namespace {
 
 enum MigratedPreferences {
@@ -234,6 +238,10 @@ void RegisterUserPrefs(PrefService* user_prefs) {
   geolocation::RegisterUserPrefs(user_prefs);
 #endif
 
+#if defined(OS_ANDROID)
+  PromoHandler::RegisterUserPrefs(user_prefs);
+#endif
+
 #if defined(USE_ASH)
   ash::RegisterChromeLauncherUserPrefs(user_prefs);
 #endif