Add Desktop iOS promotion logging to chrome ios app.

ios/chrome/browser/prefs/browser_prefs.mm

Index: ios/chrome/browser/prefs/browser_prefs.mm
diff --git a/ios/chrome/browser/prefs/browser_prefs.mm b/ios/chrome/browser/prefs/browser_prefs.mm
index 8b9f604d124aab9c91c3ac93a53c50ba961246b0..3535d386878be1770cf899ea52c17f8498e09fd8 100644
--- a/ios/chrome/browser/prefs/browser_prefs.mm
+++ b/ios/chrome/browser/prefs/browser_prefs.mm
@@ -36,6 +36,7 @@
 #include "components/variations/service/variations_service.h"
 #include "components/web_resource/web_resource_pref_names.h"
 #include "ios/chrome/browser/browser_state/browser_state_info_cache.h"
+#include "ios/chrome/browser/desktop_promotion/desktop_promotion_prefs.h"
 #include "ios/chrome/browser/first_run/first_run.h"
 #import "ios/chrome/browser/geolocation/omnibox_geolocation_local_state.h"
 #import "ios/chrome/browser/memory/memory_debugger_manager.h"
@@ -88,6 +89,7 @@ void RegisterLocalStatePrefs(PrefRegistrySimple* registry) {
 
 void RegisterBrowserStatePrefs(user_prefs::PrefRegistrySyncable* registry) {
   autofill::AutofillManager::RegisterProfilePrefs(registry);
+  desktop_ios_promotion::RegisterDesktopPromotionUserPrefs(registry);
   dom_distiller::DistilledPagePrefs::RegisterProfilePrefs(registry);
   FirstRun::RegisterProfilePrefs(registry);
   gcm::GCMChannelStatusSyncer::RegisterProfilePrefs(registry);