sending message to a Handler on a dead thread

[TigerWolf]

https://github.com/learning-android/Yamba-4/blob/master/src/com/marakana/android/yamba/RefreshService.java#L40

The above line of code will cause an error:

W/MessageQueue﹕ Handler (android.os.Handler) {529a2ee0} sending message to a Handler on a dead thread
    java.lang.RuntimeException: Handler (android.os.Handler) {529a2ee0} sending message to a Handler on a dead thread

if the username and password are empty.

I updated the code with:
Log.d(TAG, "please update your username and password");