implement code review remarks

move test to PdfReaderTest

resolves DEVSIX-1426

Autoported commit.
Original commit hash: [94756cc0ea]

Author: joris.schellekens

itext.tests/itext.kernel.tests/itext/kernel/pdf/PdfReaderTest.cs

@@ -45,6 +45,7 @@ source product.
 using iText.IO.Source;
 using iText.IO.Util;
 using iText.Kernel;
+using iText.Kernel.Utils;
 using iText.Test;
 using iText.Test.Attributes;
 
@@ -1337,6 +1338,25 @@ public virtual void FreeReferencesTest() {
             pdfDoc.Close();
         }
 
+        /// <exception cref="System.IO.IOException"/>
+        /// <exception cref="System.Exception"/>
+        [NUnit.Framework.Test]
+        public virtual void FreeReferencesTest02() {
+            String cmpFile = sourceFolder + "cmp_freeReferences02.pdf";
+            String outputFile = destinationFolder + "freeReferences02.pdf";
+            String inputFile = sourceFolder + "freeReferences02.pdf";
+            PdfWriter writer = new PdfWriter(outputFile);
+            PdfReader reader = new PdfReader(inputFile);
+            PdfDocument inputPdfDocument = new PdfDocument(reader);
+            PdfDocument outputPdfDocument = new PdfDocument(writer);
+            int lastPage = inputPdfDocument.GetNumberOfPages();
+            inputPdfDocument.CopyPagesTo(lastPage, lastPage, outputPdfDocument);
+            inputPdfDocument.Close();
+            outputPdfDocument.Close();
+            NUnit.Framework.Assert.IsNull(new CompareTool().CompareByContent(outputFile, cmpFile, destinationFolder, "diff_"
+                ));
+        }
+
         /// <exception cref="System.IO.IOException"/>
         [NUnit.Framework.Test]
         public virtual void PdfVersionTest() {

itext.tests/itext.kernel.tests/resources/itext/kernel/pdf/CorruptXRefTest/cmp_docOut.pdf renamed to itext.tests/itext.kernel.tests/resources/itext/kernel/pdf/PdfReaderTest/cmp_freeReferences02.pdf

@@ -1 +1 @@
-1b98844b04ed0e75883e0a70706d8f36bbbf932d
+94756cc0ea98649601976d5aa25cb7a56294439f