[libgdata] core: Get the content type from the response instead of hard coding it

[Debarshi Ray <debarshir src gnome org>]

commit 87389a294276de50db8e71eb35cd663b7266970d
Author: Debarshi Ray <debarshir gnome org>
Date:   Thu Apr 16 18:51:57 2015 +0200

    core: Get the content type from the response instead of hard coding it
    
    There are places where we need to hard code the content type used by
    a specific service API. eg., when we want to upload and need to know
    whether to send JSON or XML. However, in this case, we have the
    response from the server and we can find the content type from that.
    We are already doing it in a few other places, so let's do it here too.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=684920

 gdata/gdata-service.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)
---
diff --git a/gdata/gdata-service.c b/gdata/gdata-service.c
index 300824b..d49fb24 100644
--- a/gdata/gdata-service.c
+++ b/gdata/gdata-service.c
@@ -1126,6 +1126,8 @@ gdata_service_query_single_entry (GDataService *self, GDataAuthorizationDomain *
        GDataEntry *entry;
        gchar *entry_uri;
        SoupMessage *message;
+       SoupMessageHeaders *headers;
+       const gchar *content_type;
 
        g_return_val_if_fail (GDATA_IS_SERVICE (self), NULL);
        g_return_val_if_fail (domain == NULL || GDATA_IS_AUTHORIZATION_DOMAIN (domain), NULL);
@@ -1150,7 +1152,10 @@ gdata_service_query_single_entry (GDataService *self, GDataAuthorizationDomain *
 
        g_assert (message->response_body->data != NULL);
 
-       if (g_strcmp0 (GDATA_PARSABLE_CLASS (klass)->get_content_type (), "application/json") == 0) {
+       headers = message->response_headers;
+       content_type = soup_message_headers_get_content_type (headers, NULL);
+
+       if (g_strcmp0 (content_type, "application/json") == 0) {
                entry = GDATA_ENTRY (gdata_parsable_new_from_json (entry_type, message->response_body->data, 
message->response_body->length, error));
        } else {
                entry = GDATA_ENTRY (gdata_parsable_new_from_xml (entry_type, message->response_body->data, 
message->response_body->length, error));