secureConnectStart

Invoked just prior to initiating a TLS connection.

This method is invoked if the following conditions are met:

• The Call.request requires TLS.
• No existing connection from the ConnectionPool can be reused.

This can be invoked more than 1 time for a single Call. For example, if the response to the Call.request is a redirect to a different address, or a connection is retried.