RPC Binder: shutdown for too many decstrong

Not sure why I allowed this. There is no memory bug
here, but if the client is misbehaving, we shouldn't
reward it. Fail hard, fail fast.

This also fixes a deadlock when there is an unknown
binder address.

Bug: 416772676
Test: binderRpcTest
Change-Id: I0d70253ade05131de003bf0feea03694941f7e8b