Merge branch 'wip/carlosg/invalid-reads' into 'master'

libtracker-miner: Add missing ref to SPARQL buffer task

Closes #130

See merge request !278

src/libtracker-miner/tracker-sparql-buffer.c

@@ -522,7 +522,7 @@ tracker_sparql_buffer_push_finish (TrackerSparqlBuffer  *buffer,
 	task = g_task_propagate_pointer (G_TASK (res), error);
 
 	if (!task)
-		task = g_task_get_task_data (G_TASK (res));
+		task = g_object_ref (g_task_get_task_data (G_TASK (res)));
 
 	return task;
 }