[gnome-software] Do not fail to parse if the AppStream metadata contains unknown tags

[Richard Hughes <rhughes src gnome org>]

commit 82af8d3ff363dab072551ef1123e0f38c6ddd1e1
Author: Richard Hughes <richard hughsie com>
Date:   Thu Oct 24 11:03:07 2013 +0100

    Do not fail to parse if the AppStream metadata contains unknown tags
    
    This worked before if the unknown tag was in the root <application> but fails
    if it appears anywhere like <screenshots> or <keywords>

 src/plugins/appstream-cache.c |    4 +++-
 1 files changed, 3 insertions(+), 1 deletions(-)
---
diff --git a/src/plugins/appstream-cache.c b/src/plugins/appstream-cache.c
index 7d1bef8..d2f4634 100644
--- a/src/plugins/appstream-cache.c
+++ b/src/plugins/appstream-cache.c
@@ -118,6 +118,7 @@ typedef struct {
        gchar                   *url_type_temp;
        AppstreamCache          *cache;
        AppstreamTag             tag;
+       AppstreamTag             tag_last_known;
        AppstreamImage          *image;
        AppstreamScreenshot     *screenshot;
        gint                     priority;
@@ -396,6 +397,7 @@ appstream_cache_start_element_cb (GMarkupParseContext *context,
                break;
        default:
                /* ignore unknown entries */
+               helper->tag_last_known = helper->tag;
                break;
        }
 
@@ -545,7 +547,7 @@ appstream_cache_end_element_cb (GMarkupParseContext *context,
                break;
        default:
                /* ignore unknown entries */
-               helper->tag = APPSTREAM_TAG_APPLICATION;
+               helper->tag = helper->tag_last_known;
                break;
        }
 }