WIP: Pref service: use the incognito support from Chrome

chrome/browser/profiles/profile.cc

Index: chrome/browser/profiles/profile.cc
diff --git a/chrome/browser/profiles/profile.cc b/chrome/browser/profiles/profile.cc
index 0da712173e1bcaa923ff57e91d85e7787274faaa..6bf257e0dda1a415567c1b8a5d13890bd15b6486 100644
--- a/chrome/browser/profiles/profile.cc
+++ b/chrome/browser/profiles/profile.cc
@@ -246,6 +246,12 @@ bool ProfileCompare::operator()(Profile* a, Profile* b) const {
   return a->GetOriginalProfile() < b->GetOriginalProfile();
 }
 
+sync_preferences::PrefServiceSyncable* Profile::CreateOffTheRecordPrefs(
+    service_manager::Connector* otr_connector) {
+  // TODO(tibell): How do we square this circle?
+  return nullptr;
+};
+
 double Profile::GetDefaultZoomLevelForProfile() {
   return GetDefaultStoragePartition(this)
       ->GetHostZoomMap()