Check if error data is present before using it

[vinistock]

Motivation

In #2285, I made a mistake an didn't check for error.data before using it. That catch statement may rescue more than just server error. For example, if we try to send a request when the connection has already been disposed, then we'll land on that catch, but the data attribute won't exist, which would then try to read it and throw another error.

Implementation

Made two changes:

1. Started checking if data is there before accessing it
2. Started disposing of the logger, which we weren't doing before (by pushing it to subscriptions)