Fix device update / entity_id with names (#10029)

* Fix device update

* Add tests

* add test for disabled warning

homeassistant/helpers/entity_component.py

@@ -210,6 +210,15 @@ class EntityComponent(object):
 
         entity.hass = self.hass
 
+        # Update properties before we generate the entity_id
+        if update_before_add:
+            try:
+                yield from entity.async_device_update(warning=False)
+            except Exception:  # pylint: disable=broad-except
+                self.logger.exception("Error on device update!")
+                return False
+
+        # Write entity_id to entity
         if getattr(entity, 'entity_id', None) is None:
             object_id = entity.name or DEVICE_DEFAULT_NAME
 
@@ -234,7 +243,7 @@ class EntityComponent(object):
         if hasattr(entity, 'async_added_to_hass'):
             yield from entity.async_added_to_hass()
 
-        yield from entity.async_update_ha_state(update_before_add)
+        yield from entity.async_update_ha_state()
 
         return True
 
@@ -361,12 +370,14 @@ class EntityPlatform(object):
 
     def add_entities(self, new_entities, update_before_add=False):
         """Add entities for a single platform."""
+        # That avoid deadlocks
         if update_before_add:
-            for entity in new_entities:
-                entity.update()
+            self.component.logger.warning(
+                "Call 'add_entities' with update_before_add=True "
+                "only inside tests or you can run into a deadlock!")
 
         run_coroutine_threadsafe(
-            self.async_add_entities(list(new_entities), False),
+            self.async_add_entities(list(new_entities), update_before_add),
             self.component.hass.loop).result()
 
     @asyncio.coroutine