public boolean init(@NonNull PaymentSessionListener listener,
                        @NonNull PaymentSessionConfig paymentSessionConfig) {
        return init(listener, paymentSessionConfig, null);
    }
public boolean init ( @ NonNull PaymentSessionListener listener , @ NonNull PaymentSessionConfig paymentSessionConfig ) { return init ( listener , paymentSessionConfig , null ) ; }
Initialize the PaymentSession with a {@link PaymentSessionListener} to be notified of
data changes.

@param listener a {@link PaymentSessionListener} that will receive notifications of changes
in payment session status, including networking status
@param paymentSessionConfig a {@link PaymentSessionConfig} used to decide which items are
necessary in the PaymentSession.
@return {@code true} if the PaymentSession is initialized, {@code false} if a state error
occurs. Failure can only occur if there is no initialized {@link CustomerSession}.