Updated libart_lgpl23 (2.3.17 -> 2.3.19)

Oeps, this should be part of the previous commit to fix #320

x11/libart_lgpl23/libart-2.3.19-header.patch

@@ -0,0 +1,19 @@
+
+Patch found on https://bugzilla.redhat.com/show_bug.cgi?id=230571
+
+--- libart_lgpl-2.3.19/art_misc.h.extern-c      2007-01-02 00:59:22.000000000 
++0100
++++ libart_lgpl-2.3.19/art_misc.h       2007-03-01 09:19:06.000000000 +0100
+@@ -34,9 +34,15 @@
+ #include <libart_lgpl/art_config.h>
+ #endif
+
++#ifdef __cplusplus
++extern "C" {
++#endif
+ void *art_alloc(size_t size);
+ void art_free(void *ptr);
+ void *art_realloc(void *ptr, size_t size);
++#ifdef __cplusplus
++}
++#endif /* __cplusplus */