stream: accept NULL in the free function
stream: accept NULL in the free function

joshtriplett/libgit2,KTXSoftware/libgit2,Tousiph/Demo1,joshtriplett/libgit2,yongthecoder/libgit2,jeffhostetler/public_libgit2,stewid/libgit2,KTXSoftware/libgit2,saurabhsuniljain/libgit2,leoyanggit/libgit2,Tousiph/Demo1,saurabhsuniljain/libgit2,stewid/libgit2,magnus98/TEST,saurabhsuniljain/libgit2,magnus98/TEST,yongthecoder/libgit2,joshtriplett/libgit2,stewid/libgit2,leoyanggit/libgit2,jeffhostetler/public_libgit2,KTXSoftware/libgit2,KTXSoftware/libgit2,stewid/libgit2,jeffhostetler/public_libgit2,Tousiph/Demo1,joshtriplett/libgit2,leoyanggit/libgit2,leoyanggit/libgit2,saurabhsuniljain/libgit2,Corillian/libgit2,Corillian/libgit2,yongthecoder/libgit2,yongthecoder/libgit2,Tousiph/Demo1,magnus98/TEST,joshtriplett/libgit2,magnus98/TEST,jeffhostetler/public_libgit2,Tousiph/Demo1,magnus98/TEST,Corillian/libgit2,jeffhostetler/public_libgit2,leoyanggit/libgit2,KTXSoftware/libgit2,joshtriplett/libgit2,yongthecoder/libgit2,jeffhostetler/public_libgit2,magnus98/TEST,Tousiph/Demo1,Corillian/libgit2,stewid/libgit2,leoyanggit/libgit2,stewid/libgit2,yongthecoder/libgit2,saurabhsuniljain/libgit2,KTXSoftware/libgit2,saurabhsuniljain/libgit2,Corillian/libgit2,Corillian/libgit2