[evolution/webkit] Fix possible crash when writing message/rfc822

[Dan VrÃtil <dvratil src gnome org>]

commit 8a099a108ff6edd8d73a14bab43f46e11da04288
Author: Dan VrÃtil <dvratil redhat com>
Date:   Tue Feb 21 14:18:43 2012 +0100

    Fix possible crash when writing message/rfc822

 mail/em-format-html.c |    6 +++++-
 1 files changed, 5 insertions(+), 1 deletions(-)
---
diff --git a/mail/em-format-html.c b/mail/em-format-html.c
index a39fb3f..211eec3 100644
--- a/mail/em-format-html.c
+++ b/mail/em-format-html.c
@@ -1382,7 +1382,11 @@ efh_write_message (EMFormat *emf,
                         if (!puri->is_attachment && puri->write_func) {
                                 /* efh_write_message_rfc822 starts parsing _after_
                                  * the passed PURI, so we must give it previous PURI here */
-                                EMFormatPURI *p = iter->prev->data;
+                                EMFormatPURI *p;
+				if (!iter->prev)
+					continue;
+
+				p = iter->prev->data;
                                 puri->write_func (emf, p, stream, info, cancellable);
                         }