Reduce usage of FOR_EACH_OBSERVER macro in components/invalidation

components/invalidation/impl/invalidator_registrar.cc

Index: components/invalidation/impl/invalidator_registrar.cc
diff --git a/components/invalidation/impl/invalidator_registrar.cc b/components/invalidation/impl/invalidator_registrar.cc
index 903cf72451df07174d4fe1cb7b4634910bd4eadc..f9727904293375efd166477991f0b49fded0a71d 100644
--- a/components/invalidation/impl/invalidator_registrar.cc
+++ b/components/invalidation/impl/invalidator_registrar.cc
@@ -115,8 +115,8 @@ void InvalidatorRegistrar::UpdateInvalidatorState(InvalidatorState state) {
   DVLOG(1) << "New invalidator state: " << InvalidatorStateToString(state_)
       << " -> " << InvalidatorStateToString(state);
   state_ = state;
-  FOR_EACH_OBSERVER(InvalidationHandler, handlers_,
-                    OnInvalidatorStateChange(state));
+  for (auto& observer : handlers_)
+    observer.OnInvalidatorStateChange(state);
 }
 
 InvalidatorState InvalidatorRegistrar::GetInvalidatorState() const {