PDFBOX-5927: prevent dictionary key from becoming an indirect object in an object stream

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/trunk@1922608 13f79535-47bb-0310-9956-ffa450edef68

Author: THausherr

pdfbox/src/main/java/org/apache/pdfbox/pdfwriter/compress/COSWriterObjectStream.java

@@ -347,7 +347,10 @@ private void writeCOSDictionary(OutputStream output, COSDictionary cosDictionary
         {
             if (entry.getValue() != null)
             {
-                writeObject(output, entry.getKey(), false);
+                // PDFBOX-5927: topLevel true to avoid having a dictionary key as an indirect object
+                // if it already exists as such
+                writeObject(output, entry.getKey(), true);
+
                 writeObject(output, entry.getValue(), false);
             }
         }