Merge pull request #1542 from balloob/fix_race_condition

Handle Wemo startup race condition.

homeassistant/components/binary_sensor/wemo.py

@@ -45,6 +45,9 @@ class WemoBinarySensor(BinarySensorDevice):
         _LOGGER.info(
             'Subscription update for  %s',
             _device)
+        if not hasattr(self, 'hass'):
+            self.update()
+            return
         self.update_ha_state(True)
 
     @property

homeassistant/components/switch/wemo.py

@@ -63,6 +63,9 @@ class WemoSwitch(SwitchDevice):
         _LOGGER.info(
             'Subscription update for  %s',
             _device)
+        if not hasattr(self, 'hass'):
+            self.update()
+            return
         self.update_ha_state(True)
 
     @property