[evolution/gnome-3-38] Fix a memory leak when quoting headers for message replies

[Milan Crha <mcrha src gnome org>]

commit c042a301fc390a2389572f49116b35ae713d4405
Author: Milan Crha <mcrha redhat com>
Date:   Thu Jan 14 16:45:52 2021 +0100

    Fix a memory leak when quoting headers for message replies
    
    This could happen when the message did not contain expected header,
    the function returned early, without unreferencing the message.

 src/em-format/e-mail-formatter-quote-headers.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)
---
diff --git a/src/em-format/e-mail-formatter-quote-headers.c b/src/em-format/e-mail-formatter-quote-headers.c
index e0f349457e..7e99d012c7 100644
--- a/src/em-format/e-mail-formatter-quote-headers.c
+++ b/src/em-format/e-mail-formatter-quote-headers.c
@@ -147,8 +147,10 @@ emfqe_format_header (EMailFormatter *formatter,
 
                medium = CAMEL_MEDIUM (mime_part);
                txt = camel_medium_get_header (medium, canon_name);
-               if (txt == NULL)
+               if (txt == NULL) {
+                       g_object_unref (mime_part);
                        return;
+               }
 
                fmt_charset = e_mail_formatter_dup_charset (formatter);
                if (!fmt_charset)
@@ -160,6 +162,7 @@ emfqe_format_header (EMailFormatter *formatter,
 
                if (addrs == NULL) {
                        g_free (buf);
+                       g_object_unref (mime_part);
                        return;
                }
 
@@ -192,8 +195,10 @@ emfqe_format_header (EMailFormatter *formatter,
                        txt = camel_medium_get_header (medium, "x-newsreader");
                if (txt == NULL)
                        txt = camel_medium_get_header (medium, "x-mimeole");
-               if (txt == NULL)
+               if (txt == NULL) {
+                       g_object_unref (mime_part);
                        return;
+               }
 
                txt = value = camel_header_format_ctext (txt, charset);
 
@@ -207,8 +212,10 @@ emfqe_format_header (EMailFormatter *formatter,
 
                medium = CAMEL_MEDIUM (mime_part);
                txt = camel_medium_get_header (medium, canon_name);
-               if (txt == NULL)
+               if (txt == NULL) {
+                       g_object_unref (mime_part);
                        return;
+               }
 
                flags |= E_MAIL_FORMATTER_HEADER_FLAG_BOLD;