PDFBOX-5660: optimize, as suggested by Valery Bokov; closes #236

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/trunk@1928141 13f79535-47bb-0310-9956-ffa450edef68

Author: THausherr

pdfbox/src/main/java/org/apache/pdfbox/pdmodel/common/COSArrayList.java

@@ -119,7 +119,7 @@ public COSArrayList( E actualObject, COSBase item, COSDictionary dictionary, COS
     {
         array = new COSArray();
         array.add( item );
-        actual = new ArrayList<>();
+        actual = new ArrayList<>(1);
         actual.add( actualObject );
 
         parentDict = dictionary;