Remove unuseful param of the ConnectionContext

The ConnectionContext depends on the ConnectionPool.
A ConnectionPool already known the connection classes,
the configuration object and the url needed to create a new connection.

But we pass again thoses informations when we create a ConnectionContext.
This is unuseful, we can reuse thoses in the connection pool even we
want a not pooled connection.

This change removes the unuseful ConnectionContext parameters,
this also ensures that connection created with or without the pool
are created in the same ways and only at one place (the create method
of the connection pool).

Change-Id: I4bd43d202fa2774ad5dcb0f8dd05e58ba60c6009
Merge "Remove unuseful param of the ConnectionContext"