Exclude OCG dictionaries from duplication verification

Add test case to verifie OCG copying behaviour

DEVSIX-6093

Autoported commit.
Original commit hash: [9561a1aec]

itext.tests/itext.kernel.tests/itext/kernel/utils/PdfMergerTest.cs

@@ -439,6 +439,27 @@ namespace iText.Kernel.Utils {
                 ));
         }
 
+        [NUnit.Framework.Test]
+        public virtual void MergeWithSameNamedOCGTest() {
+            String firstPdfDocument = sourceFolder + "sameNamdOCGSource.pdf";
+            String secondPdfDocument = sourceFolder + "doc2.pdf";
+            String cmpDocument = sourceFolder + "cmp_MergeWithSameNamedOCG.pdf";
+            String mergedDocument = destinationFolder + "mergeWithSameNamedOCG.pdf";
+            using (PdfDocument documentA = new PdfDocument(new PdfReader(firstPdfDocument))) {
+                using (PdfDocument documentB = new PdfDocument(new PdfReader(secondPdfDocument))) {
+                    using (PdfDocument mergedPdf = new PdfDocument(new PdfWriter(mergedDocument))) {
+                        mergedPdf.GetWriter().SetSmartMode(true);
+                        PdfMerger merger = new PdfMerger(mergedPdf, false, true);
+                        merger.Merge(documentA, 1, documentA.GetNumberOfPages());
+                        merger.Merge(documentB, 1, documentB.GetNumberOfPages());
+                        merger.Close();
+                    }
+                }
+            }
+            NUnit.Framework.Assert.IsNull(new CompareTool().CompareByContent(mergedDocument, cmpDocument, destinationFolder
+                ));
+        }
+
         private void MergePdfs(IList<FileInfo> sources, String destination) {
             PdfDocument mergedDoc = new PdfDocument(new PdfWriter(destination));
             PdfMerger merger = new PdfMerger(mergedDoc);

itext.tests/itext.kernel.tests/resources/itext/kernel/utils/PdfMergerTest/cmp_MergeWithSameNamedOCG.pdf

@@ -0,0 +1,8 @@
+On Layer 1 page 1
+On Layer 2 page 1
+On Layer 1 page 2
+On Layer 2 page 2
+Hello Helvetica!
+Hello Courier!
+Hello TimesRoman!
+

itext.tests/itext.kernel.tests/resources/itext/kernel/utils/PdfMergerTest/sameNamdOCGSource.pdf

@@ -0,0 +1,5 @@
+On Layer 1 page 1
+On Layer 2 page 1
+On Layer 1 page 2
+On Layer 2 page 2
+

itext/itext.kernel/itext/kernel/pdf/PdfWriter.cs

@@ -273,7 +273,8 @@ namespace iText.Kernel.Pdf {
                 }
             }
             SerializedObjectContent serializedContent = null;
-            if (properties.smartMode && tryToFindDuplicate && !CheckTypeOfPdfDictionary(obj, PdfName.Page)) {
+            if (properties.smartMode && tryToFindDuplicate && !CheckTypeOfPdfDictionary(obj, PdfName.Page) && !CheckTypeOfPdfDictionary
+                (obj, PdfName.OCG)) {
                 serializedContent = smartModeSerializer.SerializeObject(obj);
                 PdfIndirectReference objectRef = smartModeSerializer.GetSavedSerializedObject(serializedContent);
                 if (objectRef != null) {

port-hash

@@ -1 +1 @@
-b7e566db44293a7b8e0a1af07360fd8087865331
+9561a1aecf626a4609068b87fe76b467bc41cf21