Implement new invalidations ack tracking system

chrome/browser/policy/cloud/cloud_policy_invalidator.h

Index: chrome/browser/policy/cloud/cloud_policy_invalidator.h
diff --git a/chrome/browser/policy/cloud/cloud_policy_invalidator.h b/chrome/browser/policy/cloud/cloud_policy_invalidator.h
index 5ad66dbdd7aae691ce27ac91bd3764bb8035056b..4ac4cd949fca5854696d982a13031fe5d72eb916 100644
--- a/chrome/browser/policy/cloud/cloud_policy_invalidator.h
+++ b/chrome/browser/policy/cloud/cloud_policy_invalidator.h
@@ -14,6 +14,8 @@
 #include "base/threading/thread_checker.h"
 #include "chrome/browser/policy/cloud/cloud_policy_core.h"
 #include "chrome/browser/policy/cloud/cloud_policy_store.h"
+#include "google/cacheinvalidation/include/types.h"
+#include "sync/internal_api/public/base/invalidation.h"
 #include "sync/notifier/invalidation_handler.h"
 
 namespace base {
@@ -165,8 +167,8 @@ class CloudPolicyInvalidator : public syncer::InvalidationHandler,
   // invalidation_version_ when such invalidations occur.
   int unknown_version_invalidation_count_;
 
-  // The acknowledgment handle for the current invalidation.
-  syncer::AckHandle ack_handle_;
+  // The most up to date invalidation.
+  scoped_ptr<syncer::Invalidation> invalidation_;
 
   // WeakPtrFactory used to create callbacks to this object.
   base::WeakPtrFactory<CloudPolicyInvalidator> weak_factory_;