[interchange] Fix [charge] to not populate $Vend::Session->{errors}{mv_credit_card_valid}

commit 5c6a0418fc94841d2efa9aec9db25a3874fe774c
Author: Stefan Hornburg (Racke) <[email protected]>
Date:   Thu Apr 14 19:10:27 2011 +0200

    Fix [charge] to not populate $Vend::Session->{errors}{mv_credit_card_valid}
    when payment module returned an empty error message.
    
    This happens with PayPaypalExpress when using setrequest request and
    results in [if errors]...[/if] being true but [error all=1 show_error=1]
    displaying nothing.

 lib/Vend/Payment.pm |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/lib/Vend/Payment.pm b/lib/Vend/Payment.pm
index d0a6238..8175da2 100644
--- a/lib/Vend/Payment.pm
+++ b/lib/Vend/Payment.pm
@@ -508,7 +508,9 @@ sub charge {
 
 	if($result{$svar} !~ /^success/) {
 		$Vend::Session->{payment_error} = $result{$evar};
-		$Vend::Session->{errors}{mv_credit_card_valid} = $result{$evar};
+		if ($result{$evar} =~ /\S/) {
+			$Vend::Session->{errors}{mv_credit_card_valid} = $result{$evar};
+		}
 		$result{'invalid-order-id'} = delete $result{'order-id'}
 			if $result{'order-id'};
 	}