relax assert() checks for foreign

load from buffer can have get_flags() but no get_flags_filename(),
remove assert test

TODO

@@ -1,17 +1,6 @@
 blocking bugs
 =============
 
-- try
-
-	$ vips list classes
-	...
-	VipsForeignLoadJpegFile (jpegload) ...
-	** VIPS:ERROR:foreign.c:486:vips_foreign_load_summary_class: assertion failed: (!class->get_flags == !class->get_flags_filename)
-	Aborted
-
-
-
-
 - none!
 
 

libvips/foreign/foreign.c

@@ -480,11 +480,6 @@ vips_foreign_load_summary_class( VipsObjectClass *object_class, VipsBuf *buf )
 		if( class->load )
 			vips_buf_appends( buf, ", load" );
 
-		/* Sanity: it's OK to have get_flags() and 
-		 * get_flags_filename() both NULL or both not-NULL.
-		 */
-		g_assert( !class->get_flags == !class->get_flags_filename );
-
 		/* You can omit ->load(), you must not omit ->header().
 		 */
 		g_assert( class->header );