[evolution-data-server] Do not propagate only folder-flagged flag change in CamelVeeMessageInfo

[Milan Crha <mcrha src gnome org>]

commit 8dd27632ec118c3fc737d5ca21028c9a185ef05a
Author: Milan Crha <mcrha redhat com>
Date:   Tue Nov 22 14:03:37 2016 +0100

    Do not propagate only folder-flagged flag change in CamelVeeMessageInfo

 src/camel/camel-vee-message-info.c |    7 +++++++
 1 files changed, 7 insertions(+), 0 deletions(-)
---
diff --git a/src/camel/camel-vee-message-info.c b/src/camel/camel-vee-message-info.c
index b0b3e0d..ed3a55d 100644
--- a/src/camel/camel-vee-message-info.c
+++ b/src/camel/camel-vee-message-info.c
@@ -149,6 +149,13 @@ vee_message_info_set_flags_real (CamelMessageInfo *mi,
                                 guint32 mask,
                                 guint32 set)
 {
+       /* Do not propagate the only folder-flagged flag change to the original
+          message info, because this flag is managed by the original summary/folder,
+          rather than the virtual folder. The base summary also uses it to mark
+          new message infos as flagged, which is odd for virtual folders. */
+       if (mask == CAMEL_MESSAGE_FOLDER_FLAGGED)
+               return FALSE;
+
        vee_call_from_parent_mi (FALSE, gboolean, camel_message_info_set_flags, (orig_mi, mask, set), TRUE);
 }