be more robust

Author: Vladimir Kotal

opengrok-indexer/src/main/java/org/opengrok/indexer/util/FileExtraZipper.java

@@ -77,9 +77,11 @@ private NullableNumLinesLOC findExtra(Map<String, NullableNumLinesLOC> byName, F
     private Map<String, NullableNumLinesLOC> indexExtraByName(List<NullableNumLinesLOC> extras) {
         Map<String, NullableNumLinesLOC> byPath = new HashMap<>();
         for (NullableNumLinesLOC extra : extras) {
-            File f = new File(extra.getPath());
-            String filename = f.getName();
-            byPath.put(filename, extra);
+            if (extra.getPath() != null) {
+                File f = new File(extra.getPath());
+                String filename = f.getName();
+                byPath.put(filename, extra);
+            }
         }
         return byPath;
     }