SAML2_HTTPArtifact: Avoid PHP warnings when receiving ArtifactResponse without data.
SAML2_HTTPArtifact: Avoid PHP warnings when receiving ArtifactResponse without data.

git-svn-id: a243b28a2a52d65555a829a95c8c333076d39ae1@2537 44740490-163a-0410-bde0-09ae8108e29a

sylvainmed/simplesamlphp,jschlyter/simplesamlphp,girgen/simplesamlphp,jschlyter/simplesamlphp,StudentLifeMarketingAndDesign/simplesamlphp,madmatt/simplesamlphp,maytechnet/simplesamlphp,StudentLifeMarketingAndDesign/simplesamlphp,sitya/simplesamlphp,jschlyter/simplesamlphp,BrettMerrick/simplesamlphp,BrettMerrick/simplesamlphp,maytechnet/simplesamlphp,grnet/simplesamlphp,Kunstmaan/simplesamlphp,sylvainmed/simplesamlphp,sylvainmed/simplesamlphp,gtkrug/simplesamlphp,ghalse/simplesamlphp,cwaldbieser/simplesamlphp,girgen/simplesamlphp,simplesamlphp/simplesamlphp,girgen/simplesamlphp,shoaibali/simplesamlphp,maytechnet/simplesamlphp,dnmvisser/simplesamlphp,sylvainmed/simplesamlphp,shoaibali/simplesamlphp,Kunstmaan/simplesamlphp,shoaibali/simplesamlphp,StudentLifeMarketingAndDesign/simplesamlphp,simplesamlphp/simplesamlphp,sitya/simplesamlphp,dialogik/simplesamlphp,gtkrug/simplesamlphp,sitya/simplesamlphp,madmatt/simplesamlphp,BrettMerrick/simplesamlphp,ghalse/simplesamlphp,dnmvisser/simplesamlphp,Kunstmaan/simplesamlphp,dialogik/simplesamlphp,grnet/simplesamlphp,girgen/simplesamlphp,madmatt/simplesamlphp,dzuelke/simplesamlphp,grnet/simplesamlphp,dnmvisser/simplesamlphp,jschlyter/simplesamlphp,Kunstmaan/simplesamlphp,simplesamlphp/simplesamlphp,dialogik/simplesamlphp,jschlyter/simplesamlphp,dzuelke/simplesamlphp,cwaldbieser/simplesamlphp,StudentLifeMarketingAndDesign/simplesamlphp,gtkrug/simplesamlphp,gtkrug/simplesamlphp,sitya/simplesamlphp,ghalse/simplesamlphp,dnmvisser/simplesamlphp,dzuelke/simplesamlphp,BrettMerrick/simplesamlphp,maytechnet/simplesamlphp,simplesamlphp/simplesamlphp,cwaldbieser/simplesamlphp,dzuelke/simplesamlphp,dialogik/simplesamlphp,girgen/simplesamlphp,dialogik/simplesamlphp,shoaibali/simplesamlphp,ghalse/simplesamlphp,madmatt/simplesamlphp,cwaldbieser/simplesamlphp,grnet/simplesamlphp