handle exception in android service call

common/android.py

@@ -13,11 +13,13 @@ NetworkStrength = log.ThermalData.NetworkStrength
 
 
 def service_call(call):
+  try:
     ret = subprocess.check_output(["service", "call", *call], encoding='utf8').strip()
     if 'Parcel' not in ret:
       return None
-
     return parse_service_call_bytes(ret)
+  except subprocess.CalledProcessError:
+    return None
 
 
 def parse_service_call_unpack(r, fmt):