Correct extraction of Unicode form field names

DEVSIX-1357

Author: Benoit Lagae

forms/src/main/java/com/itextpdf/forms/PdfAcroForm.java

@@ -845,10 +845,10 @@ private Map<String, PdfFormField> iterateFields(PdfArray array, Map<String, PdfF
                         parentField = PdfFormField.makeFormField(parentField.getParent(), document);
                     }
                 }
-                name = fieldName.toUnicodeString() + "." + index;
+                name = fieldName.getValue() + "." + index;
                 index++;
             } else {
-                name = fieldName.toUnicodeString();
+                name = fieldName.getValue();
             }
             fields.put(name, formField);
             if (formField.getKids() != null) {

forms/src/main/java/com/itextpdf/forms/fields/PdfFormField.java

@@ -1214,12 +1214,12 @@ public PdfString getFieldName() {
             PdfFormField parentField = PdfFormField.makeFormField(getParent(), getDocument());
             PdfString pName = parentField.getFieldName();
             if (pName != null) {
-                parentName = pName.toUnicodeString() + ".";
+                parentName = pName.getValue() + ".";
             }
         }
         PdfString name = getPdfObject().getAsString(PdfName.T);
         if (name != null) {
-            name = new PdfString(parentName + name.toUnicodeString());
+            name = new PdfString(parentName + name.getValue());
         }
         return name;
     }