Revert "MediaRoster: Don't allow rosters without a BApplication"

This reverts commit f3c2f6665f.

src/kits/media/MediaRoster.cpp

@@ -2302,7 +2302,7 @@ BMediaRoster::Roster(status_t* out_error)
 	BAutolock lock(sInitLocker);
 
 	if (be_app == NULL)
-		debugger("Warning! You should have a valid BApplication.");
+		TRACE("Warning! You should have a valid BApplication.");
 
 	if (!lock.IsLocked())
 		return NULL;