evolution does not build with latest libxml2

[Don Lewis]

On 14 May, Sergio de Almeida Lenzi wrote:
> FreeBSD 10  and 9.2 does not build
> evolution with latest libxml2
> 
> ====================================
> e-cal-backend-caldav.c:1533:28: error: incomplete definition of type
> 'struct _xmlBuf'
>                                   (gchar *) buf->buffer->content,
>                                             ~~~~~~~~~~~^
> /usr/local/include/libxml2/libxml/tree.h:104:16: note: forward
> declaration of 'struct _xmlBuf'
> typedef struct _xmlBuf xmlBuf;
>                ^
> e-cal-backend-caldav.c:1583:28: error: incomplete definition of type
> 'struct _xmlBuf'
>                                   (gchar *) buf->buffer->content,
>                                             ~~~~~~~~~~~^
> /usr/local/include/libxml2/libxml/tree.h:104:16: note: forward
> declaration of 'struct _xmlBuf'
> typedef struct _xmlBuf xmlBuf;
> ======================================

I ran into the same problem and came up with this patch that at least
allows the port to build.  I'm unable to actually test it, so it might
destroy all of your files or do something else that's evil.

--- plugins/caldav/caldav-browse-server.c.orig	2010-09-21 00:26:29.000000000 -0700
+++ plugins/caldav/caldav-browse-server.c	2014-05-14 12:55:29.000000000 -0700
@@ -979,7 +979,7 @@
 
 	soup_message_headers_append (message->request_headers, "User-Agent", "Evolution/" VERSION);
 	soup_message_headers_append (message->request_headers, "Depth", depth_1 ? "1" : "0");
-	soup_message_set_request (message, "application/xml", SOUP_MEMORY_COPY, (const gchar *) buf->buffer->content, buf->buffer->use);
+	soup_message_set_request (message, "application/xml", SOUP_MEMORY_COPY, (const gchar *) xmlBufContent(buf->buffer), xmlBufUse(buf->buffer));
 
 	/* Clean up the memory */
 	xmlOutputBufferClose (buf);