Remove enable_media_router.

chrome/browser/prefs/pref_service_syncable_util.cc

Index: chrome/browser/prefs/pref_service_syncable_util.cc
diff --git a/chrome/browser/prefs/pref_service_syncable_util.cc b/chrome/browser/prefs/pref_service_syncable_util.cc
index 2a40fa9e07297a6020b2cab72c3ee381ada06cfd..68c2f27a9eb3d47422d0aac6030f9a95f8955bf5 100644
--- a/chrome/browser/prefs/pref_service_syncable_util.cc
+++ b/chrome/browser/prefs/pref_service_syncable_util.cc
@@ -36,9 +36,7 @@ sync_preferences::PrefServiceSyncable* CreateIncognitoPrefServiceSyncable(
   // or behavior of the user should have this property.
   std::vector<const char*> overlay_pref_names;
   overlay_pref_names.push_back(prefs::kBrowserWindowPlacement);
-#if defined(ENABLE_MEDIA_ROUTER)
   overlay_pref_names.push_back(prefs::kMediaRouterTabMirroringSources);
-#endif
   overlay_pref_names.push_back(prefs::kSaveFileDefaultDirectory);
 #if defined(OS_ANDROID)
   overlay_pref_names.push_back(proxy_config::prefs::kProxy);