BLI: Make Report Missing Files display message when no files are missing

Before this, if there were no missing files, the operator would run
successfully but there would be no user feedback at all, making the
user wonder if the operator was even run.

Reviewed By: brecht

Differential Revision: https://developer.blender.org/D16585

source/blender/blenkernel/intern/bpath.c

@@ -236,6 +236,10 @@ void BKE_bpath_missing_files_check(Main *bmain, ReportList *reports)
       .flag = BKE_BPATH_FOREACH_PATH_ABSOLUTE | BKE_BPATH_FOREACH_PATH_SKIP_PACKED |
               BKE_BPATH_FOREACH_PATH_RESOLVE_TOKEN | BKE_BPATH_TRAVERSE_SKIP_WEAK_REFERENCES,
       .user_data = reports});
+
+  if (BLI_listbase_is_empty(&reports->list)) {
+    BKE_reportf(reports, RPT_INFO, "No missing files");
+  }
 }
 
 /** \} */