Handle Nonfatal_rpc_exception for non-persistent clients
Summary:
D6947335 wrapped some exceptions thrown inside `ServerCommand.handle` method with `Nonfatal_rpc_exception` and updated `handle_persistent_connection_` method to expect them.
This also changed the exceptions that `handle_connection_` (the non-persistent version) sees. All the special match cases would no longer be hit and everything goes to the generic catch-all. This mostly affects spamminess of logging (both Scuba and logfile).
I fix it here, and also make use of environment recovered from `Nonfatal_rpc_exception` that would be ignored before.
Reviewed By: ljw1004
Differential Revision:
D7207797
fbshipit-source-id:
858f1d415c2ff3e1b23e4ce0c9a4b998ed100468