Decomped registration logic into its own class.

chrome/browser/sync/notifier/invalidation_util.h

Index: chrome/browser/sync/notifier/invalidation_util.h
diff --git a/chrome/browser/sync/notifier/invalidation_util.h b/chrome/browser/sync/notifier/invalidation_util.h
index 3ca5fe9d9856e15a007b38b576b6d79f8180ddcf..92e6a6e4766706dba47ee5979aad24a0a35a3e96 100644
--- a/chrome/browser/sync/notifier/invalidation_util.h
+++ b/chrome/browser/sync/notifier/invalidation_util.h
@@ -9,12 +9,19 @@
 
 #include <string>
 
+#include "chrome/browser/sync/syncable/model_type.h"
 #include "google/cacheinvalidation/invalidation-client.h"
 
 namespace sync_notifier {
 
 void RunAndDeleteClosure(invalidation::Closure* task);
 
+bool RealModelTypeToObjectId(syncable::ModelType model_type,
+                             invalidation::ObjectId* object_id);
+
+bool ObjectIdToRealModelType(const invalidation::ObjectId& object_id,
+                             syncable::ModelType* model_type);
+
 // We need to write our own protobuf-to-string functions because we
 // use LITE_RUNTIME, which doesn't support DebugString().