Separate invalidator and sync client ID (part 2/2)

sync/tools/null_invalidation_state_tracker.cc

Index: sync/tools/null_invalidation_state_tracker.cc
diff --git a/sync/tools/null_invalidation_state_tracker.cc b/sync/tools/null_invalidation_state_tracker.cc
index 084630c99f14ae0155ee67d5b3740edbb5da5a5d..192060bf97f3a0e96d86c54b1af5c4f1b893a9bf 100644
--- a/sync/tools/null_invalidation_state_tracker.cc
+++ b/sync/tools/null_invalidation_state_tracker.cc
@@ -43,6 +43,12 @@ void NullInvalidationStateTracker::SetInvalidatorClientId(
 }
 
 std::string NullInvalidationStateTracker::GetInvalidatorClientId() const {
+  // The caller of this function is probably looking for an ID it can use to
+  // identify this client as the originator of some notifiable change.  It does
+  // this so the invalidation server can prevent it from being notified of its
+  // own changes.  This invalidation state tracker doesn't remember its ID, so
+  // it can't support this feature.
+  NOTREACHED() << "This state tracker does not support reflection-blocking";
   return std::string();
 }
 
@@ -56,6 +62,10 @@ void NullInvalidationStateTracker::SetBootstrapData(const std::string& data) {
   LOG(INFO) << "Setting bootstrap data to: " << base64_data;
 }
 
+void NullInvalidationStateTracker::Clear() {
+  // We have no members to clear.
+}
+
 void NullInvalidationStateTracker::GenerateAckHandles(
     const ObjectIdSet& ids,
     const scoped_refptr<base::TaskRunner>& task_runner,