Reduce usage of FOR_EACH_OBSERVER macro in components/

components/proximity_auth/remote_device_life_cycle_impl.cc

Index: components/proximity_auth/remote_device_life_cycle_impl.cc
diff --git a/components/proximity_auth/remote_device_life_cycle_impl.cc b/components/proximity_auth/remote_device_life_cycle_impl.cc
index a5c37bea93255687500771fbd07643f6e4aaf8b8..0095e59fdc15766ef0b1b58d207536b59a6e9f7e 100644
--- a/components/proximity_auth/remote_device_life_cycle_impl.cc
+++ b/components/proximity_auth/remote_device_life_cycle_impl.cc
@@ -107,8 +107,8 @@ void RemoteDeviceLifeCycleImpl::TransitionToState(
                << " => " << static_cast<int>(new_state);
   RemoteDeviceLifeCycle::State old_state = state_;
   state_ = new_state;
-  FOR_EACH_OBSERVER(Observer, observers_,
-                    OnLifeCycleStateChanged(old_state, new_state));
+  for (auto& observer : observers_)
+    observer.OnLifeCycleStateChanged(old_state, new_state);
 }
 
 void RemoteDeviceLifeCycleImpl::FindConnection() {