Update libxml to 2.7.7.

third_party/libxml/linux/include/libxml/xmlversion.h

Index: third_party/libxml/linux/include/libxml/xmlversion.h
diff --git a/third_party/libxml/linux/include/libxml/xmlversion.h b/third_party/libxml/linux/include/libxml/xmlversion.h
index ab3fe86bd45116e8d402bfa85becf5da662ca81d..9e849fa3796a51d56e8fd77200523fbc0184bc46 100644
--- a/third_party/libxml/linux/include/libxml/xmlversion.h
+++ b/third_party/libxml/linux/include/libxml/xmlversion.h
@@ -29,21 +29,21 @@ XMLPUBFUN void XMLCALL xmlCheckVersion(int version);
  *
  * the version string like "1.2.3"
  */
-#define LIBXML_DOTTED_VERSION "2.6.32"
+#define LIBXML_DOTTED_VERSION "2.7.7"
 
 /**
  * LIBXML_VERSION:
  *
  * the version number: 1.2.3 value is 10203
  */
-#define LIBXML_VERSION 20632
+#define LIBXML_VERSION 20707
 
 /**
  * LIBXML_VERSION_STRING:
  *
  * the version number string, 1.2.3 value is "10203"
  */
-#define LIBXML_VERSION_STRING "20632"
+#define LIBXML_VERSION_STRING "20707"
 
 /**
  * LIBXML_VERSION_EXTRA:
@@ -58,7 +58,7 @@ XMLPUBFUN void XMLCALL xmlCheckVersion(int version);
  * Macro to check that the libxml version in use is compatible with
  * the version the software has been compiled against
  */
-#define LIBXML_TEST_VERSION xmlCheckVersion(20632);
+#define LIBXML_TEST_VERSION xmlCheckVersion(20707);
 
 #ifndef VMS
 #if 0
@@ -379,7 +379,7 @@ XMLPUBFUN void XMLCALL xmlCheckVersion(int version);
  *
  * the string suffix used by dynamic modules (usually shared libraries)
  */
-#define LIBXML_MODULE_EXTENSION ".dll" 
+#define LIBXML_MODULE_EXTENSION ".so" 
 #endif
 
 /**
@@ -391,22 +391,74 @@ XMLPUBFUN void XMLCALL xmlCheckVersion(int version);
 #define LIBXML_ZLIB_ENABLED
 #endif
 
+#ifdef __GNUC__
+#ifdef HAVE_ANSIDECL_H
+#include <ansidecl.h>
+#endif
+
 /**
  * ATTRIBUTE_UNUSED:
  *
  * Macro used to signal to GCC unused function parameters
  */
-#ifdef __GNUC__
-#ifdef HAVE_ANSIDECL_H
-#include <ansidecl.h>
-#endif
+
 #ifndef ATTRIBUTE_UNUSED
 #define ATTRIBUTE_UNUSED __attribute__((unused))
 #endif
+
+/**
+ * LIBXML_ATTR_ALLOC_SIZE:
+ *
+ * Macro used to indicate to GCC this is an allocator function
+ */
+
+#ifndef LIBXML_ATTR_ALLOC_SIZE
+# if ((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)))
+#  define LIBXML_ATTR_ALLOC_SIZE(x) __attribute__((alloc_size(x)))
+# else
+#  define LIBXML_ATTR_ALLOC_SIZE(x)
+# endif
 #else
-#define ATTRIBUTE_UNUSED
+# define LIBXML_ATTR_ALLOC_SIZE(x)
+#endif
+
+/**
+ * LIBXML_ATTR_FORMAT:
+ *
+ * Macro used to indicate to GCC the parameter are printf like
+ */
+
+#ifndef LIBXML_ATTR_FORMAT
+# if ((__GNUC__ > 3) || ((__GNUC__ == 3) && (__GNUC_MINOR__ >= 3)))
+#  define LIBXML_ATTR_FORMAT(fmt,args) __attribute__((__format__(__printf__,fmt,args)))
+# else
+#  define LIBXML_ATTR_FORMAT(fmt,args)
+# endif
+#else
+# define LIBXML_ATTR_FORMAT(fmt,args)
 #endif
 
+#else /* ! __GNUC__ */
+/**
+ * ATTRIBUTE_UNUSED:
+ *
+ * Macro used to signal to GCC unused function parameters
+ */
+#define ATTRIBUTE_UNUSED
+/**
+ * LIBXML_ATTR_ALLOC_SIZE:
+ *
+ * Macro used to indicate to GCC this is an allocator function
+ */
+#define LIBXML_ATTR_ALLOC_SIZE(x)
+/**
+ * LIBXML_ATTR_FORMAT:
+ *
+ * Macro used to indicate to GCC the parameter are printf like
+ */
+#define LIBXML_ATTR_FORMAT(fmt,args)
+#endif /* __GNUC__ */
+
 #ifdef __cplusplus
 }
 #endif /* __cplusplus */