nemo-icon-container.c: Always treat desktop pseudo-files as

semi-placed icons - that is, they can have their positions stored,
then restored later, but their position can be adjusted upon placement
if their previously stored position is now occupied.

This follows up on a3cdf47

Fixes #1576

libnemo-private/nemo-icon-container.c

@@ -30,6 +30,7 @@
 #include "nemo-icon-container.h"
 
 #include "nemo-file.h"
+#include "nemo-desktop-icon-file.h"
 #include "nemo-global-preferences.h"
 #include "nemo-icon-private.h"
 #include "nemo-lib-self-check-functions.h"
@@ -5670,17 +5671,20 @@ is_old_or_unknown_icon_data (NemoIconContainer *container,
 {
 	time_t timestamp;
 	gboolean success;
+    gboolean is_transient;
 
     /* Undefined at startup */
 	if (container->details->layout_timestamp == UNDEFINED_TIME) {
 		return FALSE;
 	}
 
+    is_transient = NEMO_IS_DESKTOP_ICON_FILE (data);
+
 	g_signal_emit (container,
 		       signals[GET_STORED_LAYOUT_TIMESTAMP], 0,
 		       data, &timestamp, &success);
 
-	return (!success || timestamp < container->details->layout_timestamp);
+	return (!success || is_transient || timestamp < container->details->layout_timestamp);
 }
 
 gboolean